Slayer

by The card holder

Rating: mature
Tags: My Little Pony: Friendship is Magic, Dark, Horror, Discord, Violence, Princess Celestia, Crossover, Death, Human, Twilight Sparkle, Princess Luna, Gore
Length: 33994

Twilight reads about "The Slayer", a mysterious warrior from the distant past, and is intrigued.

In an attempt to stay on top of any potential crisis, Twilight starts reading up on as many legends as she can.

One in particular catches her interest, even though it didn't even have a full paragraph of description.

Perhaps Celestia knows what exactly this "Slayer" is?

Published 2018-08-15 20:30:02 UTC
Last updated 2020-10-28 06:41:49 UTC

Prelude

"Hey, Twilight, I'm gonna go grab some food, want anything?"

"No thanks, Starlight, I'm busy right now."

"Alright, suit yourself."

Once she was alone, Twilight let out a small sigh. Truth was, she would have loved to take a break and get a bite to eat, but her stubborn nature refused to back down just yet. The pile of books in front of her, both stacked on her desk and floating in her magic, was an obvious sign of that.

Her goal was somewhat farfetched, but at the same time one would be hard pressed to find fault with it. She had noticed that many of the beings that threatened Equestria, from Nightmare Moon to Tirek, had some amount of historical records about them, be they through proper research and evidence or legends passed down for generations.

To that end, she decided to be proactive, and start documenting any and all legends that could theoretically threaten the livelihood of ponykind at some point in the future. It was a difficult task, due in large part to the sheer number of times certain legends were mentioned across various sources, often with conflicting or extra details scattered here and there. Still, Twilight felt that if anypony could pull off such a task, it could be her.

Regardless, even if it was ultimately for the good of Equestria, spending this much time bending over books was murder on her spine.

Leaning back, Twilight straightened out her back and neck with a few audible cracks, and she took the time to survey her current progress. More than a few dozen books, condensed down into "only" a fifteen foot scroll. It helped that a majority of the legends she found were either no threat at all, or were already decidedly dealt with.

"Alright, just one more, then a break," Twilight muttered to herself, diving right back in to start scanning more pages. As luck would have it, however, she didn't have to look for long before a particular passage caught her eye.

After the defeat of Discord, Princess Celestia and Princess Luna were tasked with rebuilding a broken Equestria. However, this was not easy for them, as they soon had to quell a minor invasion from Tartarus, including The Slayer, a truly fearsome and brutal foe.

The book went on to explain the details of how Celestia and Luna helped Equestria recover from Discord's reign, but Twilight kept reading the previous sentence over and over. She already knew about the Tartarus invasion, even if it was always overshadowed greatly by Discord in history books. Instead, it was the specific mention of "The Slayer" that was new to her.

Scanning through the rest of the book showed no other use of the phrase. There was only that single sentence, but she had a feeling there was much more to it than that.

Wanting direct answers, Twilight levitated over a blank parchment and started writing a letter. Once she was done, she immediately set out to find Spike.

Celestia did everything in her power to suppress a yawn, just barely managing to hold it in until the latest noble left the throne room. Countless years of running day court, and she still found it incredibly dull.

While she took the time to appreciate the brief break, a familiar pop sounded next to her, and she caught the resulting scroll in her magic effortlessly. Surely Twilight had something more interesting to tell her about.

Celestia,

Sorry for the sudden letter, but I have a few (non-urgent) questions to ask. I was looking through some old legends, to try and get a head start on whoever might threaten Equestria next, and I found something that didn't seem to appear anywhere else, and was only mentioned in passing.

I suppose I'll get right to the point. Do you happen to know anything about something called "The Slayer"? I saw it mentioned in a history book right after you and Luna defeated Discord, but it didn't give any detail beyond the fact that they were apparently related to Tartarus in some way.

Feel free to respond whenever you find the time, like I said, this isn't urgent.

Thanks,
Twilight Sparkle

Once she reached the end of the letter, Celestia let out a sigh. She knew it was only a matter of time before Twilight decided to do something like this, but she'd be lying to herself if she said she wasn't at least a little proud of her former student.

After telling a guard near her that day court was going to end early for the day, she teleported to her chambers and immediately started writing out a reply.

Twilight,

I apologize for how sudden this is, but could you please come to Canterlot as soon as you are able? There is much I would like to discuss with you on this subject.

Celestia

Just half an hour later, Celestia was leaving her room right as an exhausted-Twilight Sparkle ran towards her, coming to a panting halt. A nearby maid offered her a glass of water, which she accepted instantly and gulped down.

Once she had regained her composure, she spoke to Celestia. "I came as quickly as I could. Had to fly most of the way here."

Celestia couldn't hide the small smirk on her face. She almost forgot that Twilight was like this. "I'm sorry, Twilight, I made this visit sound more vital than it really was."

Twilight tilted her head. "So what did you call me here for?"

"It is still very important, and I had a feeling we would be in this position someday." She turned around and started walking. "Come, I have much to show you."

Confused, Twilight fell in step behind her. The trip passed in silence, and after winding through a few hallways of the castle, they came to a familiar room.

"The Elements?" Twilight asked as Celestia walked up to the door. "But they were absorbed by the Tree of Harmony, remember?"

Celestia chuckled. "This door led to more than just the Elements, you know."

Just like before, Celestia stuck her horn into the door, causing it to swing open. As Twilight expected, it was empty.

However, Celestia simply walked inside and inserted her horn into the far wall, which also opened up, revealing a rather large elevator. Twilight was taken aback by this.

"P- Princess Celestia...?"

"Let's go, Twilight. There's something I want to show you."

The elevator went down once they were both on board, and the trip felt like an eternity. Twilight tried to figure out how far down into the mountain they were going, but eventually the scenery made her lose track.

The rock wall on all sides of the elevator suddenly opened up, revealing large, well-lit caverns. In these caverns, ponies in lab coats constantly bustled around, going from desks to tables containing all manner of strange objects. There were a few guards posted here and there, but their armor looked a lot more heavy-duty than the normal Solar and Lunar guard.

Seeing Twilight's awestruck expression, Celestia started to explain. "Long ago, not too long after defeating Discord, myself and Luna came to much the same realization as you, Twilight. For some reason, many of the threats we faced had some sort of legend behind them. So, we both created a private group of scholars tasked with searching for exactly these sorts of legends."

The elevator came to a halt at the bottom of a massive atrium, and Celestia exited, still talking. "As years went on, and more and more legendary items and beings were tracked down, I took the liberty to, shall we say, increase the scale."

One of the scientists, a unicorn who had a gold star on the shoulder of her lab coat, approached the two. "Ah, Princess Celestia. Here for another checkup? We haven't really made any progress since you last came down here."

"Actually, I was hoping to show my former student these facilities," Celestia said, gesturing a wing towards Twilight, who still couldn't stop looking around like a filly in a candy shop. "Twilight, meet Observable Aegis, she is in charge of these labs while I'm gone."

"Pleasure to meet you," she said, offering a hoof.

Twilight slowly took Aegis's hoof, giving a slow shake. "N- Nice to meet you too, Aegis."

"I guess Celestia already gave you the rundown of what we do here?" Aegis asked, already leading the two deeper into the facility.

"I've already caught her up to speed," Celestia confirmed. "Although, I wanted to show her something specific, first."

"Oh? Like what?"

Celestia leaned in a bit closer. "Could you show her to The Slayer's room?"

Aegis's fur stood on end, but only for a brief moment. "W- Why that?"

"She found a mention of him in a history book, and was curious."

Twilight came closer to the two, eyes darting back and forth, her voice equally low. "You mean The Slayer is here?"

Celestia nodded.

"Well, can't say no to the boss," Aegis said. "Right this way, then."

Twilight found it very tempting to slip away from the two and simply look at many other parts of the labs, and to see what was behind many of the closed doors they walked by, but the growing knot in her stomach kept her on track. This was all mindblowing to her so far, but why did she feel this nervous? Obviously, if The Slayer was here, then it would no longer be a threat.

Right?

Eventually, they arrived at a particularly large door, which seemed to have more guards than usual stationed around it. After Aegis spoke with one of them, they motioned to another guard in a nearby booth, who pulled a couple switches, causing the door to slide open.

The chamber inside was somewhat large, for what it contained. At the far end, illuminated by a number of spotlights, was a statue of a bipedal creature. It looked like it was wearing some form of armor, and was carrying some sort of double-barreled weapon in one claw, pointed at the ground. The other was pointing outward, and for a split second Twilight felt as if it was reaching out for her.

The chills didn't stop upon entering the room, either. If anything, they were only stronger now.

"Well, Twilight," Aegis said, "meet The Slayer."

Impression

Twilight looked back and forth between Celestia and The Slayer. "You... turned him into a statue?"

Celestia nodded. "It seemed to be the correct choice at the time. We still had the Elements ready to use, and the spell we cast before to banish the rest of the demons left him unaffected."

Twilight kept staring at him, slowly trotting forward to get a better look. "Wait, wasn't he with the demons?"

When Celestia didn't answer, Twilight turned around to find her looking away, her expression unreadable.

Twilight had a feeling she knew the answer, but asked anyway. "Was The Slayer... really a demon?"

"We're still not entirely sure," Aegis answered in Celestia's stead. "We've been unable to do any proper digging into his mind, even with Princess Luna's help. To put it bluntly, there is... well, a lot of demonic corruption surrounding his soul. Even our best mages were unable to dig too deeply before it became too much to bear."

Twilight looked to the weapon in The Slayer's grasp. "So, what was he doing when you... captured him?"

"Twilight, you are aware of the Church of Discord, correct?"

She tilted her head at Celestia's unexpected question. "Aren't those the ponies that stayed loyal to Discord, even after you defeated him?"

"That is right." Celestia looked into a corner of the room, as if lost in the memory. "At the time, Luna suspected the Church was responsible for causing the invasion from Tartarus, in some misguided attempt to 'resurrect' Discord. When we got to their largest camp..."

She looked straight at the statue. "He was already there."

Twilight gulped. "Was he...?"

"Twilight, I'm not going to sugarcoat it. The Slayer was completely brutalizing the remnants of the Church, and no matter how much they fought, they were unable to land a single blow. Not only that, but the damage he was able to deal out in return..."

Celestia shook her head, obviously trying to forget the details. "There were several dead demons scattered around, as well, but their bodies were whisked away once we cast the spell to banish all of the demons."

"But he wasn't affected?"

Celestia looked away. "In retrospect, that may have been a dead giveaway that something was different about him, but we were too concerned at the time. By the time we directly approached him, all of the ponies in the camp were either dead or ran away. It was just myself, Luna, and The Slayer."

Twilight felt her blood running cold just thinking about it. "Did... you fight?"

"We didn't give him the chance. Before anything else could happen, we used the Elements to seal him on the spot. We saw the devastation that he could cause, so we didn't want to take any chances."

When Twilight stewed over this information in silence, Aegis took the time to speak again. "Since then, some of the original scholars here tried to get as much info from scanning his mind as they could. Of course, like I already told you, that didn't go so well. Still, we were able to pull out at least a few common themes surrounding his past."

That got Twilight's attention. "Really?"

"Yeah, from what we could dig up," Aegis started, simultaneously bringing over a nearby clipboard with her magic, "ol' Slayer here is definitely related to Tartarus in some way. Just about everypony that took a look reported visions of suffering, incredible heat, all the usual stuff. Lot of blood spilling, too, but for some reason they've never been able to figure out what the blood is from."

Twilight circled around the statue, taking in the intricacies of what was no doubt some form of armor. Her head only barely reached his chest, she noted. "Have you ever tried... freeing him? To see if he could tell you himself?"

Aegis went wide-eyed, as if Twilight suggested something uncharacteristically lewd, while Celestia simply shook her head. "I have considered it in the past, but Luna ultimately talked me out of it. However, to be quite honest, now..."

She shuddered as her gaze met the statue's.

"...even if he is not a demon, I fear what he would do to us all if he got out."

For a moment, no one said anything as the weight of Celestia's statement hung in the air. It was soon broken by a newcomer, however.

"Sister, are you in here?"

Celestia instantly perked up, and turned around. "Ah, Luna. I hope you slept well?"

Princess Luna looked rather groggy, but still returned a genuine smile. "Twas a rather good sleep, until I had to wake up."

Everyone present gave small chuckles at the joke, Luna took the time to look at everyone in the room. "Ah, finally showing Twilight our pet project?"

Celestia gave a small, proud smile. "She started to investigate the same things we were, so I decided it was time to fill her in."

Luna looked past them. "I assume she was curious about The Slayer?"

"Yes, apparently she saw him mentioned in a history book."

Luna frowned. "Hmph. Didn't think it was relevant enough to be mentioned anymore." Suddenly, she seemed to notice the other pony in the room. "Oh, hello, Aegis, apologies for missing you entirely."

"No problem, Princess Luna," Aegis replied, nonchalantly waving a hoof. "I know you aren't a morning pony."

While they made small talk, Twilight couldn't help but keep looking at The Slayer. She wasn't sure why, but for some reason, she found herself endlessly curious about his true nature.

As she got closer to the statue, she absentmindedly brought up a hoof to touch it and inspect further.

"...and that's when Celestia and Twilight here came- WAIT, TWILIGHT, DON'T-"

The rest of the warning went unheard. As soon as her hoof made contact with the statue, Twilight's entire vision went red.

It was dark. All around her, Twilight could see absolutely nothing but the sheer blackness. She couldn't even see her own body, although she could still tell that everything was present and accounted for.

Worryingly, even lighting up her horn appeared to have no affect, and the darkness stubbornly stayed put on herself and her surroundings.

She also noticed that, despite the scenery, it wasn't quite silent. She could hear what sounded like distant wind blowing, as well as various unintelligible whispers.

"Hello?" she called out, her voice echoing throughout the void.

She got no answer.

Seeing no other options, she began walking in a random direction. While she was still able to walk, the floor here didn't entirely feel tangible. Even cloudwalking offered some sort of feedback, but this truly felt like she was walking on nothing at all.

As she moved, the whispers slowly grew in frequency and volume, although they remained just as incomprehensible as before.

"C- Celestia? Luna? Aegis?"

Her calls went unanswered.

Eventually, the scenery changed, ever so slightly, and she saw something finally take form in the distance, roughly the size of a pony.

"Hey!" she called out to the form, but still got no answer.

Now with a destination, Twilight broke into a gallop, trying to see who it was. Frustratingly, whoever it was, they seemed to be constantly out of focus, no matter how close she got. The most she could make out was the color green.

All the while, the whispering steadily grew more frenzied, but she paid it no mind.

Once she fully closed the distance, she brought up a hoof to try and get their attention.

The moment she made contact, she yelped and jumped back, the small touch practically burning her. At the same time, the figure suddenly came into focus, and she could almost feel her heart stop.

As she looked on, the figure rose to its full height, and no matter how much she wanted to run, her legs refused to cooperate.

The moment the figure turned around, Twilight knew who it was. At the same time, her head felt like it was splitting open, and she fell to the ground in pain.

One after another, various visions forced their way into the back of her mind, each one causing another blast of pain to wrack her body. All the while, The Slayer slowly walked towards her.

She didn't notice. Instead, all her focus was on the pain, and the visions that caused them.

An endless, desolate landscape, filled with dozens of fresh corpses.

The constant sounds of violent battle, along with the tearing of all sorts of viscera.

Incredible heat, followed swiftly with even more piercing pain, again and again.

Sometimes, she could fully make out the form of various monstrosities, followed quickly by their destruction.

All the while, the pain just kept getting worse, just kept growing, just wouldn't stop

"Twilight!"

And just like that, she was back in the facility under Canterlot castle. She remembered being shown The Slayer's room, talking with Luna, and then touching the statue, but then...

She shook her head as she slowly got to her hooves. Past that, everything was a huge blur. It felt like, somehow, it lasted both an eternity and no time at all.

As soon as she was on her hooves, she noticed that everyone was closely gathered around her. Luna looked even more tired than when she first walked in, and all of them looked incredibly worried.

"Okay, I should've told you about that," Aegis said quickly, "simply touching the statue triggers the visions in unicorns, I am so, so sorry about that."

"Are you feeling okay, Twilight?" Celestia asked.

"Y-yeah, I'm... fine." She looked back at the statue. "How long was I out?"

"Only two minutes, at most," Luna said. "Normally, ponies stay out for a bit longer, but I was able to pull you back to the waking world much more quickly."

"And, uh, don't worry about side effects," Aegis hastily added. "As long as you didn't go too deep, you'll be perfectly fine. And trust me, we'd know if you went too deep."

"In any case, you should rest for a bit," Celestia said. "We have a break room where you can lay down for a bit."

"Yeah, I'll... I'll do that..."

Celestia nodded, and led the group out of The Slayer's chamber. Before the door shut behind them, Twilight gave one last look back at the statue.

Was he really a demon? Or something else entirely?

Questions

Compared to the appearance of the rest of the facility, the break room was rather mundane. A few tables at one end of the room, with a medium-sized counter at the other side, next to a fridge. A coffee pot was currently brewing, its familiar scent filling the air.

Twilight took a few deep breaths as she sipped at her cup. Celestia had to leave, in order to "handle the no doubt numerous complaints about today's early day court closure", leaving her with Aegis and Luna.

"Is it... normal to not remember anything?" Twilight asked.

"Yeah, that happens," Aegis replied. "Just, uh, be careful next time you go to sleep. For about the next week or so, you'll probably see the visions again in nightmares."

Twilight stared into her coffee. "Oh, joy."

"Do not worry, Twilight," Luna said. "I'll be sure to help you with the worst of it, same as I have for all the researchers here. Who knows, perhaps you'll be lucky enough to have seen something new."

"I thought you said you already had a general idea of what the visions are?"

"They still vary widely," Aegis explained. "Some ponies got nothing but screaming, some got so much at once that even Luna couldn't sort through it."

Twilight took another sip. "What do you two think?"

Luna paused in the middle of sipping her own coffee. "Hmm?"

"About The Slayer," Twilight continued. "Do you really think he's a demon?"

The two stayed in silence for a bit, before Luna answered. "For a while, I was all but convinced of it. Even if he himself was not a demon, perhaps he was some kind of advanced golem created by them."

Twilight let out a "Huh" and scratched her chin. She had to admit, the concept never occurred to her, but it still made some amount of sense.

"That theory still has a lot of blanks, though," Aegis countered. "Like, if he actually was a golem, wouldn't he deactivate once his primary controller was either dead or out of range? After all, there weren't any demons left around by the time the princesses confronted him."

Twilight looked at her. "So you think he's not a demon?"

She nodded. "Although, admittedly, that thought is almost scarier," she continued. "After all, a creature capable of just as much brutality as an actual demon, if not more?" She shivered. "Kinda makes you hope they never get out."

Suddenly, Twilight had a realization. "Do you think he's related to Discord in some way?"

"We already thought of that," Luna said. "Not too long after we captured The Slayer, I dove into Discord's mind to try and get an answer from him. Even though he was less than cooperative, he still told me that he had nothing to do with him, and I had no reason to doubt him, especially after both his return and his brief episode with Tirek."

Twilight tilted her head, then leaned back. "Oh, I get it, because then he would've let him out, too."

"Besides that, as much corruption as there is around The Slayer, none of it feels remotely close to the chaos magic that Discord uses," Luna added. When she tried to take another sip of coffee, she noticed her cup was empty, and rose to get more. "In any case, he knows more or less the same as us, at this point."

"I guess I could always ask him," Twilight said. "He does live in Ponyville, now."

Suddenly, she shot up from the table. "Shoot, Ponyville! My friends are probably worried about me by now!"

Luna raised an eyebrow. "Isn't this a regular occurrence, though, you coming to Canterlot on short notice?"

The statement calmed Twilight down slightly, but she remained standing. "Well, yeah, but usually I only do that when something serious is happening."

"Still, you may be right," Luna admitted. "It might be best to return before that Trixie of yours burns down the castle."

Twilight winced. "She wouldn't do that..."

"Twilight, I see her dreams every other night. It's a wonder she hasn't set her wagon ablaze during her whole career."

"Oh yeah, Twilight," Aegis spoke up, "next time you come by, be sure to bring the list you were making of potentially threatening legends. I'd be happy to go through it with you and show you the ones we already got handled." She stopped just before she took a drink. "Oh, and, uh, maybe keep quiet about this to your friends, for now? We kinda like to operate in secret so ponies don't panic over every little complication that comes our way, so... yeah."

"I'll... be sure to. Thanks for showing me all this, Miss Aegis."

"Hey, no problem. And no need to be so formal, you're basically my boss, now."

"Oh, uh... right." Twilight cleared her throat. "Then, uh... keep doing what you were... doing?"

Aegis smirked. "Aye aye, ma'am."

"Have a good trip back to Ponyville," Luna called out as Twilight made her way back to the elevator, "and I'll see you tonight!"

While her nerves certainly calmed down by the time Twilight got back to Ponyville, she couldn't quite fight down the general sense of unease she felt.

After stopping by the castle to assure Spike, Starlight, and Trixie that everything was just fine, she decided to head straight to Fluttershy's house. Today was already proving to be a rather long day, but she did basically promise that she'd ask him about The Slayer. Might as well get it out of the way, in any case.

As she came down for a landing in front of the cottage, she noticed that Fluttershy was already outside, holding a leash tied to about four or five... were those snakes?

Making sure to keep a good distance from them, Twilight walked up. "Hey, Fluttershy. You... uh... walking your... snakes?"

If Fluttershy noticed how simultaneously confused and creeped out she was, she didn't show it. "Oh, yes. They get agitated if they stay cooped up in their cage for too long."

Twilight just stared at them, while the snakes just flicked their tongues out now and again, not a care in the world. "...right. Say, is Discord here right now?"

"Oh, yes, he's inside making tea," she said. "Why?"

"Nothing important," Twilight partially lied, "just had a few quick questions to ask him."

Fluttershy shrugged. "Okay, Twilight." Suddenly, the snakes started tugging on their leashes, almost pulling her off balance. "Well, these guys are getting impatient, so I better go now. See you later!"

"Bye, Fluttershy!"

After they waved goodbye to one another, Twilight turned to face the door to the cottage, shaking her head. Maybe Discord was rubbing off on her a bit too much...

She didn't bother to knock, instead just opening the door and walking inside. Just like Fluttershy said, Discord was inside, lounging on the coffee table with his feet propped up on the couch, drinking from... a normal pot of tea.

"Ah, Twilight, to what do I owe the pleasure of an unexpected visit?" he greeted, raising his (completely normal) teacup in greeting.

When she didn't immediately answer, he caught her staring at the tea. "What, can I not enjoy good old fashioned tea once in a while? Not everything has to be chaos one hundred percent of the time. Ironically, that would be rather predictable, wouldn't it?"

"I... guess?" Twilight shook her head. "Anyway, I was here to see if I could ask you some questions."

"Ask away," Discord said, casually hovering off the table into a nearby recliner.

"What do you know about The Slayer?"

As soon as she finished the question, it was as if the room deflated (and not in the usual Discord way). Slowly, he put down his tea and leaned forward in his seat, looking slightly more serious. "I see. Well, what would you like to know?"

Twilight gulped. Discord being serious was something she wasn't used to, and it threw her off slightly. "W- was he a demon?"

Discord laughed, but it felt hollow, like he only laughed out of obligation. "Quite the question to start with. I suppose you already talked with Tia and Luna about this?"

Twilight didn't answer, but her silence seemed to be answer enough. "In fact, Luna probably said something about me having nothing to do with him, right?"

Twilight hesitated, then nodded.

"Well, that's still true, in case you were wondering." He leaned back. "Although, I did a bit of digging by myself, actually. Whenever I escaped the first time, before I started meddling with you ponies, I paid a visit to Tartarus for myself."

Twilight recoiled. "What? Why?"

"See, I personally didn't cause their little invasion after my defeat, but I was curious if it was simply them capitalizing on the situation. And, if that were the case, I was ready to prevent such a thing from happening again. See, Tartarus is rather orderly, all things considered, and that just doesn't sit well with me."

"Right..."

"Anyway, when I looked for myself, the area just past the gates was... oddly empty. There were only a few demons here and there, and they stayed as far as possible from the gate at all times. They even purposely avoided me, funny enough, even though I was prepared for some of them to fight."

Twilight stayed quiet as she processed this. Weren't demons violent creatures by nature?

"In fact, the only thing that tried to fight me was Cerberus," Discord continued. "And only when I was trying to get in. Once I left, he just let me go, no questions asked."

Twilight gasped. "But wait, that would mean..."

Discord finished the thought for her. "He wasn't keeping things in. He was trying to keep things out."

"...why?"

Discord shrugged. "None of the demons would talk to me, and Cerberus can't talk. Although, there is one little tidbit I managed to notice."

He leaned forward again, getting face to face with Twilight. "At one point, I tried to ask one of them about The Slayer, and the moment I said his name, it was as if a bomb went off. They all turned to look at me, and just stared, up until I left. Didn't say anything, didn't attack, just backed away if I got close. And do you know what I saw in their eyes?"

As Discord looked at Twilight with one eye closed, she shook her head slightly. "What did you see?"

"Fear. Demons, known for nothing more than mindless destruction and anger, were showing genuine fear."

Twilight's mind almost went blank at this revelation, while Discord finally backed away slightly.

"So, no, I am pretty certain that The Slayer is not a demon. He's something far worse, something that demons themselves are terrified of."

While Twilight sat in stunned silence, he continued. "That still doesn't entirely answer the question of why the demons are so adamant about staying away from Equestria, or if he was some sort of tyrannical leader to them, but either way, if The Slayer managed to get out..."

He leaned in close again.

"...there's no telling how much blood would spill."

Visitation

The talk with Discord didn't do anything to ease Twilight's unease about the situation. It did leave her exhausted, however, so she decided to sleep for the night, even if it was a bit early.

Of course, just like Aegis said, the moment she was fully asleep, she was subject to a repeat of the visions she saw when she touched The Slayer, albeit less painful. Thankfully, it felt like she didn't have to suffer through it for long before Luna appeared, and managed to somehow pull her out of the worst of it.

"W-what?" Twilight asked, once she got her bearings. "Oh, hi there, Luna. Guess I'm dreaming?"

"That is correct, Twilight." Luna looked behind her, as the visions continued to flash by, now in the distance. "I don't know how many times I've seen them, yet they still make me uncomfortable every time."

"Yeah, it's..." Twilight winced. "It's something. Can you make out anything notable?"

Luna squinted, then shook her head sadly. "I'm afraid not, at least not anything I haven't seen before."

Suddenly, Twilight's eyes widened. "Oh! Discord was able to tell me a bit more about The Slayer today!"

Luna gave her a puzzled look. "Really? I thought he told us all he knew already."

"He told me that he visited Tartarus right after he broke free," she explained. "For some reason, the demons weren't even trying to get out, and they looked afraid when Discord mentioned The Slayer."

Luna looked into the distance, deep in thought. "Even demons fear him... Interesting."

"He did say that's all he could get out of them, though," Twilight finished.

"That is fine. It is still a bit more information than we had. Good work, Twilight."

Suddenly, the void around them started to fade to white.

"Ah, you are waking up," Luna said. "Continue your research, but be careful."

"Okay, Luna. See you later, then!"

Discord didn't sleep at all that night. Instead, he simply remained seated in the recliner, staring off into space. His talk with Twilight made him start thinking about things, and he wasn't entirely sure what to do about it.

Fluttershy was a bit worried, naturally, but it was easy to reassure her and have her go up to bed herself.

By the time the sun started to rise, he had made his decision, and snapped one of his claws. In a flash of light, he was now flying above the Everfree Forest, close to the bottom of a cliff face.

Discord wasted no time and dove to the base of the cliff, and after snaking his way through some trees, he came to a large cavern. Sneaking inside, he found Cerberus in much the same place as usual, sitting in front of the gate while its three heads kept watch.

He didn't even bother to use a distraction, instead just making a beeline for the space above the gates. Cerberus got up and barked furiously, but was unable to do anything in time to actually stop his entry.

The entryway of Tartarus was much the same as he remembered. The closest demons were still a good distance away, and as Discord flew closer, they still backed away, but otherwise ignored him.

This was good, because this time he hoped to go a bit deeper, to get some proper answers.

Twilight awoke peacefully, which was broken when she managed to accidentally roll off her bed. Fortunately, her pride was the only thing that was injured, and she reminded herself that the morning wasn't quite ruined yet.

She was up earlier than everyone else in the castle, which was unsurprising. It did mean that the kitchen was entirely empty, though, so that was a plus. Even still, she wasn't particularly hungry, so she just snacked on half a sandwich that was left in the fridge (no name with it, so it was free game). She also used this time to think over her options.

She could go to Discord again to try and get more out of him, but she had the feeling that he already told her all he knew about The Slayer. Likewise, going back to the princesses' lab wouldn't help much, either. She supposed she could try and visit Tartarus directly, but that seemed like not such a good idea.

It seemed like she had reached a dead end on the subject. The only way to possibly know more involved questioning either the demons of Tartarus themselves, or The Slayer. Obviously the former was out, and the latter would be impossible without letting him free, which was also probably a horrible idea while she still knew so little.

If only Celestia and Luna were able to witness his actions a bit earlier...

As she thought that, an uncomfortable thought wormed its way to the forefront of her mind. She could still use that time travel spell that Starlight tried to use, right...?

Twilight tried to shake the thought off. She had already made her promise several times to never mess with time travel again, so using it herself would only hurt their relationship and make her into a hypocrite.

Then again, she only made Starlight promise to not use that spell to change history. So there shouldn't be anything wrong with just watching, so long as she didn't change anything, right?

But that would be almost impossible. It was a transportation spell, so she'd have to be right there in order to even see anything, and her mere presence would be enough to change the timeline in potentially drastic ways.

Assuming she was actually seen.

No matter how much she tried to rationalize away the idea, her mind kept bringing up one fact. She did have a rather powerful cloaking spell somewhere in her collection, so using that in combination with the time travel spell...

Once she finished the sandwich, she made up her mind, and started heading towards the library.

The deeper Discord went into Tartarus, the more numerous demons became. However, they still remained non-hostile to him the whole time, although at some point a few of them started to watch him as he went by. The rest either continued to mindlessly mill about, or were taking part in some sort of small congregation, usually headed by bigger demons. Some sort of class system?

The landscape slowly began to change, too. Near the gate to Equestria, the area was mostly just arid, red dirt, with a few small lava flows visible in the walls here and there. As he got deeper, not only did the space seem to open up, far more than what should've been possible with the geography outside, but rock formations started to become a regular feature, many of which had markings in their own demonic language. Discord could've probably worked some magic to see what they said, but he didn't particularly care to at the moment.

Eventually, the ground disappeared entirely, and was replaced with a series of massive rock "islands" floating in a sickly yellow void, connected to the land behind him with giant chains, with bits of rock stuck in it here and there. One of the closest islands featured a rock sculpted into the skull of a demon, complete with fire burning eternally in its eyes. Unoriginal, but effective decor.

As he hovered next to the void and looked at the giant skull, Discord heard a voice. It sounded like it was both booming around him, and also inside his head slightly.

"Why are you here, outsider? This is not your realm."

"Yes, I figured that out by now," Discord said back. "Really like what you did with the place, though. It's a classic look, I can appreciate it."

"Enough of your foolishness. Explain yourself, or leave now."

"Fine, fine." Despite the warning, Discord still poofed up a reporter's microphone, holding it out in front of him. "I was wondering if you could answer some questions of mine about a certain someone."

The voice was silent for a brief moment. "Who do you speak of?"

"I feel like you already know who. Perhaps 'The Slayer' rings a bell?"

Even though there were no visible demons in the immediate area, Discord still felt like there were countless eyes staring at him the moment he said it.

"So... It appears you know about The Doom Slayer."

Discord cocked an eyebrow. "Doom Slayer? A bit of an overdramatic title, if you ask me."

"If you knew the true power of The Doom Slayer, you would not jest so lightly."

"Oh? Sounds like he has a history here. Do tell."

And so, the demon recounted the tale of The Doom Slayer, and his eternal quest to vanquish all of Hell. Discord listened intently as he was told about his undying rage, his almost incomprehensible speed and power, and his limitless brutality, all of which was used for the sole purpose of crushing anything and everything demonic, in many, many realms across the multiverse, as well as the deepest pits of Hell itself.

"So let it be known, chaos spirit," the voice finished, "so long as The Doom Slayer remains entombed, we shall not touch your realm, for fear of setting him free once more."

Discord kept himself from letting out a gasp. "So, you know that we have him, then?"

"Indeed, we have been watching your realm for centuries, to ensure that he remains imprisoned. But know this, we are still watching, and we know that one of your kind is dangerously close to letting him escape."

"One of my kind...?" Discord muttered to himself, before his eyes went wide. "Oh dear."

The voice continued. "Should we see that he is being set free, we shall invade your realm again, until he is sealed once more."

Discord didn't offer any response, and instead turned around and started flying as fast as he could. His teleportation wouldn't work until he was at least outside of the gates, back in Equestria.

Hopefully he had enough time to stop Twilight from unknowingly bringing a second Tartarus invasion.

Witness

Thanks to Twilight's meticulous organization of her library, it took no time at all for her to retrieve the spells she needed, along with a history book in order to confirm her destination.

After finding both the correct date and rough location of that certain Church of Discord camp, Twilight found herself hesitating slightly. She shook it off quickly, though; there was clearly a mystery to be solved, here, and she was dead set on finding out the truth.

Taking a deep breath, Twilight walked into the center of the library, lit up her horn, focused on the spell, and vanished in a flash of purple.

Despite being many, many years in the past, Twilight still managed to recognize some of the scenery around her once the usual teleportation disorientation wore off. One of the upsides of living so close to the Everfree Forest, she presumed.

Shadows passed by suddenly, and Twilight looked up to see armored pegasi flying above the trees, along with the occasional glimpse of otherworldly, grotesque beings, the two groups usually in combat.

Looked like a demon invasion, alright.

After engaging the cloaking spell, Twilight started walking forward. The history books mentioned that the camp was in a clearing, so she simply had to follow the trees until they thinned out enough.

It wasn't long before the strategy paid off, and she came across a collection of ragged tents nestled between the trees, with a couple dozen ponies wearing robes walking about. There was much less aerial activity here, but she could tell that even the ponies of the Church were keeping at least one eye on the skies at all times.

Closing the distance, Twilight was glad to see that none of them even acknowledged her presence. There was a small elevated platform near the center of the camp, with more robed ponies talking in low voices around it. Just behind the platform, there was a crude recreation of Discord carved out of wood, a few ponies taking the time to bow to it.

Twilight idly wondered if Discord himself knew about the Church, or if he even cared.

Suddenly, there was a rustling at the treeline, and everypony in the camp, including Twilight, whirled around to see a group of demons march forth, their numbers rather large. Their sizes and shapes varied greatly, with a few even being seemingly restrained by others, as if they were no more than animals. Regardless of their exact form, each one was grotesque in their own way, and struck fear into Twilight no matter where she looked.

The ponies around her clearly felt the same way, and concerned murmurs started to circulate.

"Tis the demons, nay?"

"By Discord, there's so many!"

"S- Should we stand and fight?"

"No, my brothers and sisters, stand down for now."

Twilight turned to the last voice, making sure to maneuver herself so that she was out of the way of any sort of accidental collision. One of the robed ponies had a small, ornate necklace, signifying them as a leader of sorts. He walked forward to meet the demons head on, the others falling into step behind him, albeit much more nervously.

The demons, curiously, did not attack. They seemed to have a similar conversation among themselves, as a particularly large demon, which looked like a horrifying, pink version of a minotaur, started to take the lead of their own group.

The two parties met at the edge of the camp, and stopped in place, staring at each other. The ponies were filled with very obvious unease, while the demons had entirely unreadable emotions, assuming they had emotions at all.

Finally, the leader of the Church spoke up, his voice loud enough for everyone present to hear. "My brothers and sisters! Verily, this is a sign from the lord Discord himself! He wants not the reign of two false princesses, and so these demons are here to aid us by overthrowing the throne!"

Suddenly, he knelt down, his voice just as loud as before. "We shall fight with you, fine warriors of chaos!"

The rest of the ponies seemed concerned at this turn of events, but quickly fell in line, the rest of the crowd kneeling down behind their leader. The demons took this in, looked between each other, then seemed to reach an agreement.

The lead demon simply motioned his head towards a part of the formation, and began walking away, with about a third of the demons staying behind. The ponies noticed this and started to slowly rise up, but remained in place as the remaining demons started to filter into the camp. Clearly, the ponies of the Church were conflicted about whether or not to cower, since the demons weren't attacking any of them.

While it wasn't the reason she came back, Twilight still found herself fascinated by what she had just observed. Nothing in the history books mentioned that the Church of Discord allied itself with the demons, even if it sort of made sense in hindsight that they would.

Suddenly, there was the distant sound of an explosion, and everyone, pony and demon alike, stopped what they were doing to look in that direction.

Twilight felt her stomach drop, especially when another explosion went off, this time much closer.

Perhaps there was a reason the Church's demonic alliance was never written down.

While everyone was facing away from her, Twilight decided to grab a spare robe from one of the tents. It was dirty, and smelled like things she didn't want to think about, but it at least made for a decent backup plan if her concentration broke enough to disrupt the cloaking spell.

She emerged back into the open just in time to hear yet another explosion, this one coming directly from the edge of the clearing. While she didn't see any signs of it, there was instead a splash of red from the trees, staining the grass.

And right behind the spray of blood, was the entire reason she was in the past.

The Slayer.

He was currently reloading the same weapon he wielded as a statue, and Twilight tried to take in as much detail as she could at this distance. His armor was a deep green, save for the helmet, which was entirely grey, save for a single small spot of red; although whether or not that was blood was unclear.

Despite the distance, Twilight could feel her heart rate increase as she saw the figure that had been on her mind since she first heard about him.

The rest of the camp seemed to share her sentiments, as they all went incredibly still at the sight of the armored figure. Even the demons, she noted, were frozen to the spot, as if they themselves could not believe what they were seeing. Meanwhile, the ponies were much more confused, but they dared not do anything, lest they anger their new demon overlords.

The Slayer finished reloading his weapon as he walked over the spray of viscera, his gaze flowing over the entire population of the camp. From this distance, Twilight couldn't make out a face, or even if he had a face at all.

Once The Slayer was satisfied with his distance from the camp, he stopped. Weapon ready, but not aimed, his helmet still scanning between everything in the camp, as if trying to take everything in at once.

Twilight noticed that he cracked his neck as he looked on, and she felt chills run down her spine.

Perhaps this was a huge mistake on her part.

Before she could entertain the idea of slipping away to teleport back to her own time, one of the demons let out a loud hiss, and made a beeline straight for The Slayer.

Once it closed the distance, he didn't even budge, and instead brought his weapon up.

With another deafening explosion, the attacking demon was reduced to little more than a spray of blood and meat, Twilight's eyes wide at the sudden and catastrophic amount of gore she played witness to.

Just as the spray of blood hit the ground, all hell broke loose.

All at once, the ponies started screaming and panicking, running for cover in the tents or simply cowering to the ground. At the same time, the collection of demons let out their own shrieks and hisses, before charging The Slayer. One of the demons summoned a fireball in one of its claws, and sent it hurtling towards the warrior.

The Slayer was slow before, but as soon as the fireball started to close in, he became a blur of movement, quickly running out of the way and moving to meet the demons head on, weapon at the ready. The first demon he fired at was a bit too far to be reduced to giblets like its brethren, but it was still enough to cause them to stagger.

The Slayer took advantage of this, and sprinted the rest of the way towards the demon. Once it was in reach, he grabbed its head before slamming it into the ground, sending out a splash of blood as its skull was reduced to pulp.

Another demon tried to use the distraction to attack The Slayer from behind, but he caught on just in time to spin around, delivering a punch hard enough to tear right into the demon's chest, sending more blood onto the grass.

Twilight had a hard time keeping her breakfast down. Even without a weapon, The Slayer was able to turn demons to mulch with just his claws!

The battle continued, but Twilight's gaze was drawn elsewhere. One of the demons had stayed behind with the ponies, and started doing... something to a few of them. There was a flash of red, the pony would scream, and then they'd slowly stand up, before shuffling towards The Slayer, their eyes blank.

Admittedly, Twilight was not shocked by the development. Demons were rumored to be able to perform possessions of ponies, so this made sense to her.

What was more surprising was what happened after a few ponies were successfully possessed. "Members of the Church!" the leader called out, now on his hooves and reaching for a nearby spear, "our chaotic overlords have an enemy! We shall assist them!"

A few ponies slowly voiced their agreements, causing the rest to follow suit, as each one grabbed a weapon and started galloping into the fray, interrupting the demon before it could finish its possessions.

Twilight was curious as to how this would play out, even if the results would be... less than pretty.

Her attention was now back on The Slayer, who had already amassed a number of bodies around the clearing. She noticed that he was actually quite fast, able to dodge just about everything the demons threw at him. At some point, the rest of the demons that passed by seemed to join the fight, as there were even more demons than before.

Not that it seemed to faze The Slayer at all.

She also noticed that his weapon was different, now. While the previous one only held two barrels, this one had... three? No, nine, and they all spun in a circle while firing at the creatures, each shot being its own small explosion.

At least, until he transformed the weapon so the barrels were far more spread out. Then the sound became a constant, loud drone, the shots turning even the larger demons in front of him into little more than a pile of meat after a few seconds of sustained fire.

By now, the cultists managed to reach him, and tried to attack with their own weapons. Their intrusion into the fight seemed to surprise him slightly, as The Slayer took a direct hit from a sword into his helmet. The attack bounced off harmlessly, but he still whirled around at the attacker, and appeared to hesitate upon seeing it was a pony.

The hesitation didn't last, however, as the attacks continued, both from demons and the ponies of the Church. The leader was the next to attack, but he was halted by The Slayer effortlessly snapping his spear in half, before taking the sharp end and jamming it into the pony's chest.

Twilight winced, but forced herself to keep watching. Unfortunately, the battle started to become obscured by nearby tents, so Twilight crept around it to keep up.

This was incredibly poor timing, as the moment she could see The Slayer again, a stray fireball hit the tent right next to her. Twilight panicked and jumped away, and while she avoided being set ablaze, her concentration broke enough for the cloaking spell to drop.

She was glad she picked up the robe earlier, because a few demons gave her a glance thanks to her newfound visibility, but then proceeded to ignore her anyway in favor of attacking The Slayer.

Speaking of, he had become even more of a brutal, blood-spilling whirlwind. It seemed that, every other time Twilight got a look, he was holding a different weapon. Other than the two she already saw, she spotted a smaller weapon that appeared to be reloaded with a pumping mechanism, a large tube that fired rockets, a solid white device that shot small blue balls of energy, and even...

Was that a chainsaw?!

Twilight could feel her stomach turning at the sight of The Slayer butchering a demon with the woodland tool, carving right through its limbs with little effort. Once he was done, he simply started using one of his other weapons, and just left the demon corpse to fall apart.

As the body count grew, Twilight started to notice a trend. While the demons were absolutely annihilated in all manner of ways, the way he treated the ponies was... relatively tame. Sure, he still struck them down in brutal ways with no hesitation, but it seemed like he was prioritizing quick, minimally painful deaths for them.

As opposed to the demons, which were subject to just as quick, but likely much more agonizing deaths, usually in several pieces, assuming they weren't reduced to red mist.

All the while, The Slayer never once slowed down or staggered. Even when he was struck by an attack from a demon, he would immediately retaliate, and then simply continue fighting. She could tell that he still felt pain, by the way he flinched and otherwise reacted to attacks, but he still never stopped the slaughter.

Eventually, the bloodshed got to Twilight, and she had to look away to empty her stomach. As she did, she also noticed that the camp was pretty much entirely on fire now, and that some of the ash was already starting to stick to her fur and tail.

She ignored it, however, as she walked further from the camp, and slightly closer to the battle. She wanted to reengage the cloaking spell, but at this distance she had to keep an eye on any stray shots, from either the demons or The Slayer, so she didn't have the time to focus long enough.

Hopefully, once she saw enough, she'd be able to high-tail it into the woods.

By now, the ponies were all dead, and only a handful of demons were left to challenge The Slayer. While most of them only lasted long enough to receive a face full of firepower or a fist through the skull, there was one that Twilight recognized as the supposed leader of this group of demons, which appeared to be strong enough to take several shots from The Slayer's weapons.

It wasn't long before they were the only two fighters left, and Twilight watched with rapt attention as they continued their dance of death, The Slayer avoiding every lunge and fireball given by the demon while returning fire with his own weapons.

However, before a decisive blow could be struck, the sky lit up bright white, and The Slayer, the demon, and Twilight all looked up to see a huge magical wave passing over the land, and soon passing right over them.

They all watched as it seemed to dissolve the remains of any demons it touched, while leaving the bodies of the Church ponies, as well as the blazing inferno that used to be their camp. It passed over Twilight with no issue, and she turned to watch as it approached the combatants.

The demon turned to The Slayer and made one last desperate swipe, but was too late as the wave impacted him and seemed to absorb him within, its roar being carried along with it.

And so, only The Slayer was left, standing in the middle of a bunch of burnt grass and dead ponies. Suddenly, he snapped around to stare directly at Twilight, and she froze.

She had gotten a bit too close while watching the fight, without noticing.

Twilight knew that she had to run, she was wearing the same robe as the cultists he just killed, but she couldn't bring her legs to move an inch.

At any moment, she expected him to bring up that double barreled weapon and end her life, but it remained pointed at the ground, as the stare-down continued. This close, Twilight could see that, while he was now splashed with blood, that spot of red she had seen on his helmet earlier was actually some sort of symbol, the significance of which she had no knowledge.

Just as she thought she was going to pass out from fear, The Slayer turned his head to the sky, and Twilight forced herself to follow his gaze. There, she saw two blurs approaching fast from the sky, one dark blue and the other a bright gold.

This was enough to kick Twilight into action, and she started sprinting madly towards the treeline. She heard the sound of two figures landing just as she dove into the foliage.

Before she got too far in, however, she stopped.

She knew that she had to return to the present as soon as possible, if she didn't want to disrupt the timeline and get in massive trouble, but she couldn't help herself.

Slowly, she crept back to the edge of the forest, to sneak a look at what was about to happen.

Sure enough, Princess Celestia and Princess Luna were both standing there, wearing the Elements of Harmony, wearing their old armor, and glaring directly at The Slayer, who simply stood in place and glared back.

"Tis odd, sister," Luna said. "The spell did not return this one."

"Indeed," Celestia agreed, before taking a step forward. "What is your business here, creature?!"

The Slayer offered no response.

"Cease this foalishness," Luna said, stepping next to Celestia. "If one prison shall not hold a demon, than another shall have to do."

The Elements on her chest started to glow, and Celestia sighed.

"You are right, Luna."

Her own Elements started to glow, too, and The Slayer tensed up slightly, as if ready to attack at a moment's notice. Shortly after, a massive rainbow shot out from the princesses, before arcing down and landing on The Slayer.

Though he still made no noise, The Slayer very visibly struggled against the magic, and managed to reach one arm out towards the princesses, his weapon still lowered. Alas, it would not help, and it was not long before he was fully encased in stone, in a pose that Twilight very much recognized.

Once the Elements powered down, Luna wiped her forehead. "Twas... oddly simplistic, was it not?"

"Nevermind that, sister," Celestia said, "I saw a survivor of the Church flee into the woods. We should search for them."

Twilight's blood ran cold as Luna nodded. "I'll look from the skies, then. You assemble the guards to bring this... creature back to the castle."

They both launched into the air in opposite directions, and Twilight thanked every deity she knew that Luna thought she went a lot farther than she actually did. Wasting no time, she fired up her horn and started running through the time travel spell as fast as she could.

Just before she went back to her own time, Twilight gave one last look at the imprisoned Slayer.

Taking a deep breath, Twilight walked into the center of the library, lit up her horn, focused on the spell, and vanished in a flash of purple.

About five seconds later, there was another flash of purple, and Twilight reappeared, wearing a tattered robe and with her legs and tail mostly coated in ash. Once she was on stable ground, she started hyperventilating, everything she just witnessed starting to finally catch up with her. In an attempt to cope, she started running through all the facts she discovered with her irresponsible experiment.

One, The Slayer was, with one hundred percent certainty, an enemy of the demons.

Two, the hatred he appeared to possess towards demons did not carry over to ponies, but that did not stop him from killing them if they attacked first.

Three, Celestia and Luna were being entirely honest with her about their brief encounter with him.

The thinking was enough to make Twilight calm down, and she quickly realized the state she was in, as well as the robe she had inadvertently taken from the past with her. Casting a quick disintegration spell on the robe, followed immediately by a cleaning spell on herself, Twilight started galloping to the nearest window.

She knew enough, now, to make a decision.

The Slayer was no demon at all, he was their enemy.

And an enemy to demons could prove a vital asset to the protection of Equestria.

Right?

Besieged

Once they were certain that The Slayer had moved far enough away from the shelter, Twilight and Aegis started leading the survivors back to the entrance. They stopped to gawk at the carnage left behind by the warrior immediately outside the shelter, but quickly moved on.

Thankfully, it seemed that he was drawing all the attention from the demons now, as they reached the entrance elevator entirely uncontested.

That didn't stop Aegis from being cautious, however. "One of you pegasi guards, fly up and see what the situation is topside."

A guardsmare saluted. "Yes ma'am!" She flew off, slipping just above the elevator before ascending the shaft.

Twilight took this time to do a full headcount of the ponies with them. While it was more than she expected, it was still less than she would have hoped.

"Did he tell you anything?" Aegis suddenly asked her.

"W-what?"

"The Slayer. Did he... say anything to you, when you freed him?"

Twilight hesitantly shook her head. "I didn't really have time to ask him many questions, but he did nod when I asked if he was the demons' enemy."

Aegis sighed. "Sorry if I sounded a bit harsh on you back there, but... Well, you understand, we still barely know anything about him. Although, given the circumstances, I probably would've done the same thing, if I was there."

Twilight thought for a moment, before making a decision. "I know for a fact he only attacks ponies if they attack him first. We'll be fine."

"...how exactly do you know that?" Aegis asked. "Sure, he didn't hurt you or anypony here, but that doesn't mean he treats everypony like that."

"Well, funny story-"

At that moment, the guardsmare came flying back down, looking somewhat panicked. "There's demons topside, too!"

Twilight's blood ran cold while the ponies around her started to murmur worriedly. Aegis, meanwhile, was back to all business. "How are the casualties?"

"I couldn't say for sure. Luna and her guards are just barely holding them back, and according to her they're already starting to soften up their assault."

"The main entry point probably is down here, after all..." Aegis thought out loud, before nodding to the guard. "Thank you."

"So, what do we do?" Twilight asked.

Aegis thought for a moment, scanning the surrounding area. "Set up a temporary camp here. Once we receive word that the demons are gone up top, we'll get everypony out of here."

Twilight looked down the hall they just came through. "What about Princess Celestia...?"

Aegis put a hoof on her shoulder. "Go ahead and go to her. We can handle things here."

Twilight wanted to protest, but quickly fought it down. "Okay. Stay safe, okay Aegis?"

Aegis smirked. "Is that an order?"

The two shared a light chuckle, before Twilight took off, galloping down the hall.

As she got deeper into the lab, the sounds of combat grew louder again, so she probably still had time before The Slayer reached Celestia.

Hopefully she could arrive in time to defuse whatever situation might occur.

The Slayer certainly made it easy to follow him. Once Twilight made it back to the shelter, all she had to do was follow the trail of demon corpses and body parts, and try not to step in too big a pile of blood.

She considered flying, but by now the smoke collecting at the ceiling was starting to become just thick enough to choke anypony who got up there. She didn't trust her flying enough to skim the ground without issue, so she just resigned herself to tracking a little blood in her wake.

As the sounds of explosions, demonic growls, and tearing viscera grew louder, Twilight eventually caught The Slayer in the lab's mess hall, where he was doing his best to make it live up to that name. Demons were coming in at almost all sides, and he was doing an expert job at bouncing from one demon to another, constantly pumping them full of lead and/or ripping them to pieces with his hands.

Twilight almost found herself captivated by the bloody show, but shook her head and headed elsewhere. She had more important things to do than watch a thousand-year-old warrior work.

While it was impossible to tell which labs were the Delta-Four labs, due to the state of destruction the area was in, it was thankfully rather easy to spot thanks to the magical force field projected in front of the door. A few possessed ponies were beating at it, but it seemed to be doing nothing.

Firing up her horn, Twilight quickly teleported past the ponies and the force field, and knocked on the door. Just like before, a somewhat panicked voice answered her.

"W- Who is it?"

"It's Twilight Sparkle, I'm here to see Princess Celestia!"

There was some discussion on the other side, before the door slid open. She quickly filed inside, and took stock of the situation in front of her.

Unlike the shelter, this room was almost entirely filled with guards. The only non-guard pony was deeply focused on a door at the opposite end of the room, which was being protected by a golden force field while a large horde of demons tried to claw their way past it.

Celestia looked over at the sound of the door closing, and forced herself to put on a smile. "Oh, Twilight, thank goodness you're okay. How are Aegis and the others?"

"At the entrance right now. Demons invaded above ground, too, but Luna and her guards are fighting them off.

Celestia seemed conflicted by the news: horrified that demons were also in the castle proper, yet relieved that her sister was on top of it. "And what of The Slayer?"

"He's... in the mess hall, right now," Twilight said. "He was a bit... busy when I came by."

"Busy?"

"He was fighting the demons."

Celestia let out a thoughtful "Hmm." After putting a bit more focus on the door, she continued speaking. "You wouldn't happen to know how The Slayer managed to escape, would you, Twilight?"

Twilight looked to the ground. "After the demons started invading, I... well, I panicked, and I was convinced that The Slayer was an enemy to demons, so..."

Celestia shook her head slightly. "Do not worry, Twilight, I am not upset at you. Given the situation, it would make sense to use such... drastic measures."

Suddenly, Celestia's horn went out, and Twilight was ready to freak out, but stopped as she noticed that the shield was still holding. A few nearby unicorn guards seemed to take over maintaining the shield, their own horns lit up as they focused on it.

Now free of the need to concentrate, Celestia walked over to Twilight. "How long do you suppose until The Slayer reaches us?"

"Impossible to say. He moves fast, but he's focusing on the demons right now, and it seemed like they wouldn't stop coming for him."

"I see." Celestia started walking away, towards a corner of the room. "In that case, perhaps I should take the time to somehow disguise myself. While I trust that he is not hostile to ponies, since the survivors are safely at the elevator, I admittedly have no idea how he'll react to seeing me."

Twilight looked to the floor. "Yeah, that makes sense..."

"So, how exactly were you so sure about why we should free The Slayer?" Celestia suddenly asked.

Twilight froze up. "U- uh, well..."

As Celestia kept looking at her, like a disappointed parent, one of the guards near the entrance door suddenly gasped as his horn went out.

"Holy...! Something big just hit the shield! It broke!"

Nearby guards instantly took up defensive positions around the door, while the guard responsible for the shield fired the spell up again. For a brief moment, there were no sounds, save for the collection of demons still clawing at Celestia's shield, as everypony in the room held their breath.

And then, there was a knock on the door.

It was loud, but steady, and all the guards looked between each other in response. None of them moved for the door controls, however.

Once again, the knocks rang out, louder this time. Whoever was on the other side, they did not like being ignored.

Celestia and Twilight seemed to reach the same conclusion about who it was. "Keep the door closed!" Celestia called out. "Wait until I-"

Her orders were cut off, as the knocking was instead replaced with a horrible grinding noise, forcing nearly everypony in the room to fold their ears against their head. Slowly, the door was forced open, until it was just wide enough for a certain bipedal figure to walk through.

The guards instantly readied their weapons against him, but started backing up once they recognized who it was. The demons, too, seemed to fly into a frenzy at the sight of him, becoming even more agitated as they kept trying in vain to get past the shield.

The Slayer scanned the room, paying no mind to the spears and crossbows pointed his way, until his gaze locked onto Celestia and Twilight. Both of them froze under his vision, and he started walking towards them.

Twilight went to step forward, to try and defuse the situation, but the moment she moved a hoof, The Slayer shot her a glare that paralyzed her with fear.

The guards started to move in on him, keeping their weapons trained, especially as he got closer and closer to Celestia. At some point, one of the guards managed the courage to shout "Halt!"

However, the order went completely unacknowledged by The Slayer.

Soon, he was now almost face to face with Celestia, whose eyes were still wide as she stood in place. After a moment, she took a deep breath, closed her eyes, and bowed her head slightly.

"Hello again, Slayer," she said, her voice betraying no emotion besides... acceptance?

He just continued staring at her, although Twilight noticed that he was slowly forming his hands into fists.

Not noticing, Celestia continued. "I would like to... apologize for the way I treated you in the past. I know now that-"

Celestia didn't get to finish, as The Slayer suddenly wound up and punched Celestia directly in the snout, causing her to let out a yelp as she fell to the floor with a small blood spray.

While Twilight found herself far too shocked to do anything, the guards started to do two things. Some of them panicked, and started freaking out. Others started charging The Slayer, their weapons ready while they gave out battle cries.

In response, The Slayer turned around to face them, which was enough to make several guards hesitate in their charge. Only one guard actually kept the attack, and swiftly embedded his spear into The Slayer.

Or, at least, he tried to. The spearhead failed to penetrate his suit at all, and his momentum meant that the spear quickly snapped in half, and he found himself barreling right into The Slayer's leg.

Once he recovered from his daze, he looked up to see The Slayer looking down at him, at which point he started seriously reconsidering all of his life choices.

At that point, a lone crossbow bolt flew into The Slayer's helmet, ineffectively bouncing off. He quickly snapped his view up to the offender, which caused somepony in the line of guards to let out a yelp as they cowered behind their comrades.

Before anything else could occur, Celestia shakily raised a hoof. "S- Stop attacking!"

Everyone in the room snapped their attention to the princess, who was unsteadily rising back to her hooves. She was very noticeably bleeding from both nostrils, but otherwise seemed not much worse for wear. Twilight in particular noticed this, since she had seen exactly what a punch from The Slayer could do to a living creature.

He was holding back.

Celestia quickly brought up a hoof to cover her snout, in an attempt to make herself look more presentable. "It was... an understandable action," she admitted, her voice slightly nasal due to the damage to her snout. Despite the situation, Twilight couldn't help but spot the ghost of a smile behind her hoof. "So, are we even, Mister Slayer?"

As usual, The Slayer didn't say anything, and simply nodded as he started walking towards the shield holding back dozens of demons.

Twilight found herself at a complete loss. "What the hay just happened?"

Celestia used some magic to reshape her snout, wincing as she did so. "I believe that was payback for imprisoning him."

As Twilight tried to process this, she noticed The Slayer walking up to one of the guards who had a crossbow. The guard cowered under his gaze.

Unceremoniously, The Slayer reached out and grabbed the crossbow for himself, as the guard ran away to the other guards. After inspecting the weapon for a bit, he shrugged and kept walking towards the shield, tinkering with the weapon slightly in a way Twilight couldn't make out.

Once he was directly in front of the shield, he turned around and pointed to Twilight, before pointing to the shield, then behind him.

Understanding his intentions, Twilight created a shield spell of her own, trapping The Slayer between two different color force fields.

"Let the other shield down!" she called out to the guards. They seemed hesitant to do so at first, but a confirming nod from Celestia helped them make the decision.

Their horns went off, and the golden shield dissipated. As soon as it did, The Slayer fired the crossbow into the horde, which Twilight noticed now had some sort of cylindrical object on the bolt. It embedded itself into an unlucky demon's head, and a moment later the object exploded, reducing all the demons around it into little more than red paste.

The Slayer was in the fray immediately after, doing his usual routine of carving demons into pieces with either his weapons or his fists. Several of the guards were clearly disturbed by the display, and even Celestia winced slightly at some of the more gruesome actions.

While The Slayer was doing his thing, Twilight turned to Celestia. "So, about how I knew about him..."

"Yes, Twilight?"

Twilight let out a deep breath, and decided to get it over with quickly. "I went back in time to see for myself what happened just before you imprisoned him."

Celestia was quiet for a moment, and Twilight forced herself to look from the ground to her eyes.

"I see," Celestia eventually said. "Did you decide to do this based on what Discord told you?"

"...yes."

Celestia let out a small hum. "So, were you the 'survivor' we spotted running from the camp?"

Twilight winced as if she was struck. "Yes..."

Celestia sighed. "While I'm a bit disappointed that you would try to use time travel again, I suppose this was for the better. I would hate to imagine how today would have gone had we not freed The Slayer as early as you did."

Suddenly, the chamber that The Slayer was fighting in started to glow ominously. "What's going on?"

Celestia seemed equally nervous. "The device is activating? That can't be good."

They both moved closer to Twilight's shield, trying to see what exactly was going on. The Slayer was still locked in combat, but they couldn't see any reason for why the ancient teleporter was now activating.

As the fighting continued, the glow increased in intensity, until nopony could see through it. Celestia started to order the guards to do something, but it was quickly drowned out by the sound of the device turning on, a sort of electrically-tinged magic sound. Soon after, the glow died down enough that they could look inside, and found the chamber entirely empty of living things. All that remained was a portion of the demon corpses left by The Slayer.

Twilight quickly lowered her shield, and they all quickly filed into the chamber. As the guards fanned out to make sure that there were no demon stragglers, Twilight and Celestia headed to the device in the center of the room, which was still glowing faintly.

"Where did they go?" Twilight asked.

"It's difficult to say," Celestia said. "The demons were coming directly from Tartarus, but..."

She fired up her horn, in an attempt to trace where the magic in the device teleported them. After a moment, she stopped, her eyes wide.

"Twilight, we need to go, now."

As Celestia started galloping away, Twilight struggled to keep up. "W-what?! Why?"

"Because that teleporter apparently sent them to just a few miles outside of Manehattan."

Discord finally made it back into Equestria proper, and he immediately took to the sky to see what was going on.

In the distance, he could make out a few rising plumes of smoke around Canterlot.

"Oh, no..."

Looking back down to Ponyville, he was relieved to see that, for the moment, it was still peaceful.

Still, since he was apparently too late, he knew it wouldn't stay that way.

Snapping his claw, he teleported right to the front of Fluttershy's cottage, just as she was leaving the house.

"O- Oh, Discord!" she said, only slightly phased by his sudden appearances by now. "How are you?"

"Fluttershy, we have a problem. Help me get everypony in town inside Twilight's castle."

Her smile was replaced with a deeply concerned expression. "Why?"

"Because Tartarus is about to come here."

Raining Blood

By the time Twilight and Celestia had given the all-clear to the survivors of the lab to head topside, the demons had all but vanished entirely. When they headed back into the castle proper, they were just in time to see the guards starting the cleanup process, clearing away rubble, trying to scrape burn marks off the walls, or piling up piles of demon viscera and corpses into carts, presumably to study in the lab once things calmed down.

Princess Luna was in the middle of this, wearing her own personal armor as she directed members of her night guard around. Her stoic facade broke upon seeing Celestia and Twilight, and she gave out a relieved smile before dismissing her guards and heading over.

"I am pleased to see you two are alright," she said, instantly moving in for a quick nuzzle with her sister. If Celestia noticed the small patch of demon blood that rubbed onto her from the action, she didn't react to it.

"I am glad you're safe, as well," Celestia said, before her face grew grim. "Casualties...?"

Luna let out a sad sigh. "We lost a number of guards during the battle, we haven't taken full role yet so we don't know who. Thankfully, we have confirmed that no civilians have perished." She looked past them to the elevator, which was already being loaded with a cart full of demon parts. "And the labs?"

"It was... far worse," Celestia said, bluntly. "We lost a large amount of ponies, both civilian and guard."

The two shared a sad look, but Celestia pressed on. "However, as tragic as it is, we have more... urgent matters."

Luna's posture shifted noticeably, her eyes going back and forth between Twilight, Celestia, and the nearby Aegis, who was busy consoling the surviving scientists. "Is it related to what happened here today?"

Deciding to be direct, Twilight spoke up. "The Slayer is free."

"What?!"

Luna's outburst caused nearby guards to pause in their actions, before hastily resuming at Luna's commanding glare. "What do you mean, he's free?"

Celestia just looked to Twilight, who shuffled uncomfortably. "When the invasion started, I... panicked, and decided to release The Slayer."

"...I see. And where is he now?"

"While he was fighting the demons, the ancient teleporter activated," Celestia explained. "He's now somewhere just outside of Manehattan."

"Then we must go," Luna said, already starting to walk away. "We know not if he can be trusted."

"Ah, I wouldn't worry about that, Princess."

All of them looked upwards at the new voice, revealing Discord casually hovering in the air above them.

"Enough of your games, Discord," Celestia spat, "do you know something we don't about the situation?"

Discord floated down to their level, uncharacteristically serious, all things considered. "Very well. To make a long story short, I took a small trip to Tartarus to do some research of my own."

"And what did you find?" Luna asked, not bothering to give the others time to react.

Discord grinned, but it was a ghost of the smile he usually wore. "The demons are invading because The Doom Slayer was freed."

Twilight felt as if the words pierced right through her. Was this... her fault?

"'Doom' Slayer?" Celestia asked.

"It's what the demons refer to him as. And assuming they told me the truth, he's been their number one enemy for countless eons, even longer than I've been around." Seeing the state Twilight was going into, Discord hastily added, "He was the only one keeping them from invading other realms."

This did calm her nerves slightly, but only enough to not let the guilt consume her. She at least knew that agonizing over her decision could wait until the situation was fully under control. "And what about the demons," she suddenly asked. "Where have they gone?"

"They're probably focusing mostly on combating The Slayer," Discord said. "But I don't know how much they'll try to terrorize Equestria in the meantime. To that end, I went ahead and had the whole town evacuated into your castle. Starlight said something about 'Emergency Plan Delta', so I figured you'd know about that."

Twilight sighed in relief. At least her friends and neighbors in Ponyville would be safe.

"What of other cities?" Celestia asked.

"That's where you and I will come in, Tia. As ironic as it sounds, I'll do what I can to help you keep order in cities, and keep the demons at bay."

"And what of Manehattan?" Luna asked. "Who will go after The Slayer?"

"I'll go," Twilight cut in, interrupting all of them. "I... I let him out in the first place. Hopefully, if he'll listen to any of us, it'll be me."

Luna nodded. "Then I shall go with you. If what Discord says is true, and the demons will focus on him, then it would help to have a capable fighter by your side."

Celestia ignored her sister's thinly veiled bragging as she started walking off. "In any case, we should all prepare, then. This is not a problem that can be solved with the magic of friendship, so we must be ready for the worst."

After a trip to the mostly-undamaged armory, where Celestia put on her own personal armor and Twilight made due with a spare set of normal guard armor, they parted ways, Celestia and Discord heading west of Ponyville to start, with Twilight and Luna making a direct line for Manehattan.

The flight took about ten minutes, during which Twilight brought Luna up to speed about what exactly The Slayer did, and where his loyalties seemed to lie. Luna had simply nodded in response, but said nothing.

By the time they could see Manehattan over the horizon, it was obvious that something was very, very wrong.

Smoke was rising from the city center, and even from their elevation, they could see a massive crowd of ponies fleeing from the city entirely.

Fearing the worst, the two of them made their way down as quickly as they could, landing in front of a local police officer who seemed to be in charge of the evacuation. He was surprised by the sudden appearance of Luna and Twilight, but he quickly recovered.

"Oh, thank goodness you're here!" he said. "It's been mayhem in the city, and- and I don't know what the hay's going on!"

"Were you under attack?" Luna asked, her voice gentle, yet firm.

"Yeah, but it was by nothing I ever seen. They were like the stuff of nightmares! I'm making sure everypony gets out, but no way am I going back in there!"

Luna nodded in understanding. "Keep up the evacuation, then. We'll go in and see for ourselves."

The officer nodded as he resumed directing the stream of citizens, while Luna quickly took back to the air, Twilight following right behind her.

The further into the city they got, the worse the situation appeared. The outer areas only had a few scattered fires and concerning blood stains, but the entire downtown area was completely unrecognizable.

Apart from the myriad fires that were spread among the buildings, it looked as if the roads had been literally paved with flesh, often looking as if it had grown straight onto the walls of nearby buildings, as well.

Speaking of buildings, the ones that weren't collapsed completely had been entirely taken over by this otherworldly, grotesque display, as buildings were often held together by little more than pillars of flesh, twisting in shapes that should not have been structurally possible.

To say nothing of the stench, which was almost enough to make the both of them vomit from the air as soon as it hit them.

"What in the...?" Twilight gasped, unable to finish her sentence. Is this what awaited Equestria if the demons were able to roam free?

Below them, they could see a number of figures moving across the destroyed cityscape with ease, which Twilight recognized as more demons. At some point, they had been spotted, and sent a few fireballs their way to try and shoot them down, but it was easy to simply weave around them, given the distance.

"Where could The Slayer be?" Luna asked, both to herself and to Twilight. "Surely he would not abandon the city entirely?"

As if in answer, at that moment they spotted a particular set of ruins get blown to bits, as another figure ran out from it, the demons quickly converging on it.

Twilight knew who it was before she even got a good look, and she dived down to perch on a particularly tall piece of rubble, Luna following her.

Sure enough, knee-deep in the carnage was the one they had been looking for.

The Slayer, or as Discord claimed the demons knew him, The Doom Slayer.

By now, Twilight had grown numb to his methods, but this was Luna's first time seeing it, and she found herself equally in awe and repulsed by his skills.

"So... what's the plan?" Twilight awkwardly asked, not bothering to whisper due to the cacophony of battle below them.

"Hm? Right, uh..." Luna looked at The Slayer and the horde of demons converging on him, which seemed to be enough to make up her mind. "I shall go down and assist him."

"What?! But-"

"Hush, Twilight," Luna said, pulling out her sword with her magic. "Though it has been quite some time since I fought in a battle of this scale, I assure you my skills have not dulled with age."

Before another word could be said, Luna spread her wings and flew directly into the battle, immediately using her momentum to smash a demon underhoof.

Twilight just watched, terrified as Luna began fighting the demon horde from the opposite side of The Slayer. If he noticed the additional help, he didn't appear to acknowledge it.

For her part, Luna was nowhere near as effective in combat as The Slayer, but she was still more than able to keep up with the demons now targeting her. She fought with a sort of grace, easily able to combine sword use, hoof strikes, and blasts of magic into her fighting style. She wasn't killing demons as fast as The Slayer, but she was still keeping them at bay all the same.

After some time, the demons seemed conflicted on whether they should attack The Slayer or Luna, and seemed to choose whoever happened to be closer at the time. Twilight didn't spot any sort of coordination on their part, but judging by the way they fought, they seemed to operate purely on overwhelming numbers and strength, rather than tactical genius.

Eventually, it seemed that the immediate area was running out of demons, as the horde grew thinner and thinner. Much to Twilight's growing dread, it wasn't long before the group thinned out enough that The Slayer and Luna were now in direct line of sight with each other as they fought. Thankfully, The Slayer seemed to acknowledge her as an ally, and very clearly took care to not shoot at her.

The one exception was when a demon managed to slip behind Luna without her notice, and lunged right for her, only for The Slayer to dive in to intercept the demon's flight path, quickly redirecting its skull into the ground to add to the growing pile of corpses. Luna noticed the assistance, but quickly moved on to fighting other threats.

It wasn't long before all but one demon had been slain, which Luna finished off as she knocked it to the ground and drove her sword into it. Seeing that the battle was over, The Slayer began walking up behind Luna. Once again panicking, due to what happened to Celestia, Twilight chose that time to fly down to join them. "Wait!"

Luna looked over at her interruption, curiously, while The Slayer only gave her a glance as he kept walking. "What's wrong, Twilight?"

As soon as she said that, Luna caught sight of The Slayer walking towards her, until he stopped right in front of her. Though shocked by his proximity, Luna still gave a respectful nod. "I have been told about your fight against the demons. With that in mind, I would like to-"

Just as Twilight feared, Luna's apology was cut off as The Slayer hit her with a punch right in the snout. However, unlike Celestia, it wasn't enough to completely knock her down, and it was easy to see the rage filling her face as she got back up, her own blood streaming from her nose to join that of the demons on the ground. Twilight could only watch, horrified, as Luna reflexively swung her sword at The Slayer in response.

He easily caught the blade mid-swing, and proceeded to effortlessly yank the sword straight out of her magical grip, causing both Twilight and Luna to balk. He then threw the sword, blade first, at the ground in front of Luna, embedding it in the fleshy surface of the street. Without giving her a second look, The Slayer simply started walking away, heading deeper into the city.

Luna stood there, stunned, before she came to her senses and quickly pulled her sword from the ground. This time, though, Twilight was quick to get in front of her before she could chase The Slayer down. "Luna, stop!"

"Thou witnessed it, the cur attacked me!" Luna spat. "I will not stand for such disrespect!"

"Luna, please, he did the same to Celestia, too!"

That was enough to make her regain control of herself. "What?"

Twilight chuckled nervously. "I guess that's his way of paying you two back after you... imprisoned him."

Luna stood there for a moment, before slowly sheathing her sword, followed by reshaping her snout, much in the same way Celestia did. "Very well, then. Apologies for letting my anger get the better of me."

Now that the battle was behind them, Twilight took the time to inspect the ruined city around them. "Just... what are they trying to do?"

"It's part of their plan, I assume," Luna explained. "Back when they invaded after Discord's defeat, they had done something similar to some of the larger villages before we expelled them with the Elements. Still, they had never done so to this scale before..."

The answer presented itself in the back of Twilight's mind, but she did her best to not think about it, and simply tried to ignore the sound of flesh squishing underhoof as she walked.

Up ahead, in the direction The Slayer left, they could already hear the sounds of more combat.

"At least he wastes no time," Luna commented, starting to walk ahead in the same direction. "Whatever his mission here is, I feel it would not hurt to assist him, for the time being."

Twilight nodded in agreement, and they both sped up to rejoin The Slayer.

Wrath

Following The Slayer was trivial, as his path of carnage was easy to track even in the midst of the flesh-covered city. There were still a few stray demons and possessed ponies here and there, though, forcing Luna to take care of them while Twilight did her best to remain out of the fight. While she knew combat spells, she was still hesitant to begin killing living beings, even if they were demons.

Luna's combat prowess was still more than enough to get them through the city unscathed, constantly following The Slayer's bloody path. Even though he was gaining far more attackers, he breezed through them with relative ease. The few times they caught up enough to catch sight of him again, they both noticed that he was managing to advance forward at the same time as fighting off the hordes; if he ever stopped, it was only long enough to cave in a demon's skull, before they'd lose sight of him in the chaos once more.

The number of demons slowly grew fewer, and by the time Luna and Twilight finally caught up to The Slayer for good, they had a brief moment of peace. Now that they weren't in immediate danger, Twilight tried to observe where exactly they were going.

While most of the buildings were now unrecognizable, due to either their collapse or the demonic influence overtaking them, the one that The Slayer stopped at appeared to be a shop of some kind. The entire front wall had been demolished by the ground in front of it erupting, but it was still largely traversable.

In the midst of the rubble and bloodshed, Twilight could make out what looked like cages, as well as a few signs that were just intact enough to make out animal silhouettes.

"A pet shop..." Twilight muttered to herself.

"It appears so," Luna said. "Mr. Slayer, why did you stop here?"

As expected, he did not answer, but this time he didn't even move at all, as if he didn't hear her.

Concerned, Twilight walked to his side. "Are you... okay?"

He just remained rooted to the spot, staring at a certain corner of the store.

Twilight followed his gaze, and spotted the remains of a cage, twisted apart as if it were nothing more than plastic. The nearest legible sign held the figure of a rabbit, and now that Twilight looked closer, she could barely see a severed rabbit's foot caught on an edge of the cage.

She winced. As much brutality as she saw today, the thought that not even the animals were safe hit her slightly.

Slowly, The Slayer reached down and took the rabbit's foot off of the mangled metal, and brought it up to his helmet.

By now, Luna also noticed what he was so fixated on. "Vile creatures, not even sparing the pets. But was this really worth stopping for?"

Twilight didn't give any sort of answer, however, as she noticed that The Slayer's hand was starting to shake, ever so slightly. Not only that, but the hand that wasn't holding the paw was starting to ball into a tighter and tighter fist, to the point where she was afraid he'd manage to snap his entire hand off from the pressure.

And then, for the first time since his awakening, Twilight heard The Slayer make a noise.

Breathing.

Breathing that slowly got heavier and heavier, yet remained perfectly steady.

All the while, his shaking was slowly becoming more noticeable.

"Is everything alright?" Luna asked, concerned. "Should we-"

Before she could finish the question, a demon crawled into the open front of the store, and let out a hiss.

The instant the demon made a noise, The Slayer dropped the paw, threw aside his weapon, and leapt straight to the store's front.

The demon didn't even have a chance to react as the Slayer's fist impacted its chest, instantly reducing its entire body into several chunks, leaving the legs to awkwardly flop to the ground as the most intact piece.

Twilight and Luna's eyes both went wide. As strong as they had seen the Slayer to be, this was on a whole other level.

Instantly, the Slayer was moving again, sprinting back into the streets to meet a small horde of demons that had amassed during the downtime. The Slayer went to work, reducing several demons to the same state as the first one, while others were executed in far more brutal ways.

One demon was unlucky enough to be cleanly bisected down the middle, while another had a hole punched straight through its chest. Next, The Slayer jumped onto the back of a particularly large demon, where he proceeded to tear off the beast's entire right side of its torso. Without missing a beat, he then ripped its horned head from its neck, and jumped down to impale another demon on the horns, before reducing the result into a pile of meat with a single stomp.

Luna and Twilight could only watch, dumbstruck, as the carnage continued. This was unlike The Slayer's usual fighting style; if he was brutal before, this was absolutely barbaric. He no longer cared about avoiding damage, instead ignoring fireballs thrown by the demons entirely in favor of clearing the distance as soon as possible, where he would enact whatever swift, bloody end he felt like.

Once the violence became too much for her, Twilight instead shifted her focus to The Slayer's discarded weapon, and picked it up in her magic to inspect.

This was the double barreled one, which seemed to be a favorite of his based on his earlier fights. Mindful not to pull the trigger, she instead operated a lever on the top of the weapon, which caused it to fall into two separate pieces, connected via a hinge. The moment she did that, a pair of red cylinders popped out, rattling on the floor.

The cylinders in question appeared to be made of some sort of plastic, with a metal cap of some kind at one end. A quick magical deconstruction revealed that it was used to store a number of small metal balls, and what looked like black powder.

Her study was interrupted as a demon was sent flying into the store, landing at her and Luna's hooves, still alive. It tried to claw at them from the ground, before The Slayer grabbed its legs. The demon let out a cry as he pulled it back into the fight, where he immediately swung the demon so hard that its leg was amputated, while the rest of his body went flying. The Slayer then used his newly acquired limb on another demon, jamming the leg bone straight through its skull with a sickening noise.

Twilight fought down the urge to vomit, and dropped the gun and its ammo from her magic immediately.

Even Luna found herself taking a cautious step backwards. "By the stars... What has come over him? Has he always been this powerful?"

Twilight did not say anything, as she simply closed her eyes to try and block out the gruesome imagery. It only did so much, however, considering she could still easily hear the sound of tearing flesh and snapping bones.

Eventually, the sounds of battle stopped, and Twilight opened her eyes to see The Slayer standing in the middle of a massive pile of gore and viscera, his armor completely drenched in blood. He was still tensing himself for a fight, but when no more demons presented themselves, he slowly started to calm down, and after a moment, he started walking back towards the store.

Twilight and Luna both gave him a wide berth as he went to pick up his weapon. He gave Twilight a glance upon seeing that it was unloaded, but simply replaced the dismantled shells with new ones without pressing the issue.

Before he left, he knelt back down and grabbed the rabbit's foot again. After looking at it for a moment, he surprisingly gently closed his fist around it, before placing it on a section of the store counter that was still standing. Once that was done, he nodded at both ponies, and continued walking through the rear of the store. Though still confused and perturbed by his behavior, Twilight and Luna still followed.

The Slayer's path appeared to be the faster route to the heart of the city, and he cut through a few other buildings in the process. The closer they got to the center of the city, the more twisted and corrupted the architecture became. There was even a flow of lava making its way through a few parts of the city. Twilight and Luna flew over it easily, while The Slayer was able to cross with previously unseen acrobatic skill, easily hopping from one chunk of building to the next.

Twilight had a little trouble processing this. Just how many tricks did he have up his sleeve? Was there even a limit to what he could do?

Was he genuinely on their side, or only using them?

As they traveled, fighting off the odd demon here and there, they eventually came to the edge of a cliff, which led down into the most heavily corrupted part of the city.

The buildings' old forms were no longer recognizable at all, as they twisted and bent around each other and themselves, held together with pillars of flesh and strange bolts of red lightning. The lava flowed down into what was essentially a crater, creating an infernal lake that only certain sections of buildings could penetrate above.

And near the middle of this mess was a large, glowing structure of some kind. The shimmering around it confirmed that it was a portal, and Twilight was disturbed to notice that it looked like an altar that was comprised entirely of mangled and mashed-together flesh. Several possessed ponies were lingering around the portal, while other demons hopped from building to building or lazily glided through the air, while even more slowly filtered from the portal itself.

None of the demons had spotted them yet, and Twilight was surprised to see that The Slayer didn't immediately jump down into a fight. Instead, he was looking from one end of the crater to the other. Perhaps he was studying the placement of the demons? Or was he simply trying to get a grasp of traversable terrain?

"So, that's what they were trying to do last time," Luna whispered, just loud enough for Twilight to hear. "Have you seen this before, Slayer?"

He just nodded, and kept scanning the environment. Eventually, he seemed to find what he was looking for, as he took a few steps back, preparing for a running jump.

Neither of the ponies stopped him, and he leapt an incredible distance down into the crater onto an exposed collapsed building, the landing seemingly doing nothing more than making him stumble slightly before he got back up.

Both Twilight and Luna hesitated to follow him in immediately. While they could easily avoid the lava by flying, the heat was starting to get to them, and being grounded in any way would most likely be a death sentence.

Instead, they decided to hang back and watch The Slayer work.

It wasn't long before demons spotted him, but he largely ignored them and charged for the altar, only killing demons that happened to be in the way. Once he was at his target, he thrust a fist into the fleshy structure, and tore out... something, causing the entire portal to shake, and followed by many more demons flooding into the crater, either through the portal or by teleporting in with a brief storm of red energy.

They all advanced towards The Slayer, and the slaughter began.

From their vantage point, Twilight and Luna watched him go to work. He was no longer showing the same sheer strength and lack of self-preservation that he had in front of the pet store, and was instead back to his "normal" level of brutality as he effortlessly carved away at the incoming demons, often hopping between sections of buildings.

However, the number of demons kept growing, and The Slayer was taking slightly more hits than usual in his fight. They still weren't enough to provide any actual damage, from what they could see, but it was getting to the point where demons were coming in slightly faster than he could put them down.

One such demon, a large, red flying sphere, apparently spotted the ponies on its way towards The Slayer, and decided to go after them instead. Luna noticed this, and quickly sent her sword into its single eye with her magic, before retracting it. The blinded beast began to freak out, spitting balls of energy in random directions until it careened into the side of the building they were perched on, where it ended up tumbling into the lava.

When it didn't come back up, Luna cleaned the blood off her blade and faced back towards The Slayer. "I shall assist him once again. If..." She paused. "If I am unable to return, contact Celestia immediately."

Before Twilight could offer any sort of response, Luna was off, flying above and through the hordes of demons as The Slayer fought them back on whatever solid ground he could find.

Twilight was very tempted to join in, as well, but decided that she lacked the killer instinct that The Slayer or even Luna held. Instead, she prepared a remote teleport spell and kept a close eye on both the fight and her surroundings. The moment Luna appeared to be in mortal danger, she planned to bring her back before too much damage was done, hopefully.

The Slayer... well, he's clearly been able to handle himself, so far.

Even if he seemed rather unstable. Why did the death of a rabbit trigger so much sheer rage from him? What did the demons do to inspire such anger in the first place?

...what would he do once the demons retreated from Equestria?

'You do not understand the things that you tamper with.'

Twilight's eyes bugged out as her head whirled around. "Who's there?!"

'Because of your actions, The Doom Slayer has been freed, and we will forever torment your realm as a result.'

Realizing the voice was coming from within her own head, Twilight began to cower. Who was-?

Wait, the voice called him "The Doom Slayer."

Fearing the answer, she asked, "Are you... a demon?"

'You should not ask questions you already know the answer to.'

"But- how-?"

'When you freed The Hell Walker, you were in his mind for a brief time- and now, through that, we can contact you as we so please.'

The Hell Walker... another title for The Slayer?

She shook her head, steeling herself. "Whatever you're here for, I won't agree to it."

'We shall see. After all, this suffering and torment upon your land... it is your own doing.'

That gave her pause. "I..."

'The blood of the innocent is yours to bear, Twilight Sparkle.'

Tears started welling in her eyes. "No! I didn't... I..."

'No mortal ever understands the gravity of their actions. However, we can offer you a method of... redemption.'

She said nothing, and the voice continued.

'For now, The Doom Slayer is free once more, and will certainly return to Hell to continue his eternal crusade against our very existence.'

At that moment, The Slayer's chainsaw echoed over the sounds of battle, as if to punctuate the statement.

'If you are able to seal him once more, and keep him contained for eternity, we would cease our invasion of your realm, and leave you in peace.'

At first, she wanted to immediately reject the offer, but as Twilight thought, she realized the gravity of the situation. The Slayer, by fighting in Tartarus- no, by fighting in Hell, was able to protect other realms and dimensions from the demons. However, as long as he was still up and about, ponies were dying...

She was beginning to realize that the stakes were far larger than she ever could have imagined.

'We urge you to make a decision quickly,' the voice pushed. 'We know the power is available to your kind, and the longer you are indecisive, the more innocent souls we claim. And who is to say that The Doom Slayer will not see fit to punish your kind alongside us?"

Gritting her teeth, Twilight Sparkle made the most difficult decision of her life.

"I..."

"I will never help you, or any other demon. Not now, and not ever."

'Foolish mortal,' the voice growled, making her fold her ears back out of reflex. 'We saw fit to provide your realm with a way to escape damnation, and yet you refuse out of arrogance. Once we have conquered your world, we will see to it that your soul is sentenced to only the most unforgiving and unthinkable torment. Untold agony and suffering shall be your fate, as well as the fate of your loved ones, for longer than time itself. We suggest that you carefully weigh your options and reconsider.'

With that, the voice went away, and Twilight let out a breath she didn't notice she was holding.

And then she started hyperventilating as what she just did dawned on her.

What had come over her? Why was she so quick to dismiss the demons, and so bluntly? True, she would've decided that anyway, but...

She shook her head. She had more important things to worry about for the time being.

Looking back down at the fight, she was glad that Luna was still up and fighting just fine. She had more than a little blood on her by now, but judging by how she was still able to move and fight at full capacity, it was likely that none of it was hers.

Of course, The Slayer was also doing just fine for himself, even as swarmed as he looked. He never gave the demons a stationary target, and he hopped between buildings effortlessly as he fired into the hordes. On more than one occasion, he even used one of the flying demons as stepping stones, after jumping up to tear them apart like their brethren on the ground.

The portal looked even less stable than it did before, too; evidently one of them had damaged it more during the fight. On top of that, the demons were finally started to lessen in number. Looked like they were finally about to end this nightmare.

At that moment, the portal seemed to shimmer in place, as a large group of sizable pink demons came forth. In fact, Twilight recognized them as the same kind as the one that The Slayer had dueled in the past, before the Elements banished all of demonkind back to where they came from.

Only now there were several of them.

They roared in unison as they stepped forward, even treading lesser demons under their hooves as they marched towards The Slayer.

Luna was the first to challenge them, trying to fly from behind The Slayer, but unexpectedly, he grabbed her by the tail and yanked her back to the ground, behind him. She clearly protested, even if Twilight couldn't hear what was being said, but she was far more interested by what The Slayer did next.

Like usual, he simply put his current weapon behind him and another one just "appeared" in its place. However, this was a new one, and it was quite big, from what Twilight could see.

Big, and glowing a bright green.

The Slayer fired, and Twilight almost had to shield her eyes from the ensuing flash of green light. The space around the end of the gun literally appeared to distort itself, before an even brighter green ball shot into the air. This time, Twilight did have to shield her eyes.

When she looked again, there was not a single trace of any of the large demons. The only thing between The Slayer and the portal was several pools of blood and a few pieces of melted flesh, along with a genuine red mist spreading into the air.

Twilight's jaw dropped as her mind tried (and failed) to process what just happened. Did that weapon just "erase" the demons? Vaporize them, even?!

Luna was equally bewildered, but quickly shook it off as she joined The Slayer in mopping up whatever demons were left. Once the area was clear, The Slayer went straight to the base of the portal, and ripped out yet another piece.

The portal began to flicker in and out, before the entire altar collapsed into itself, the portal vanishing with it.

Almost as soon as it did, it released a red-hued shockwave, and Twilight gasped as she ducked down in response. When it passed over her harmlessly, she looked up, confused.

The shockwave spread throughout the city, and from what she could tell, it was similar to the one that the Elements had caused, getting rid of any demonic presence it passed over.

As it did so, the building Twilight was perched on started to plummet, and she yelped as she took to the air. All around her, other buildings shared the same fate, as the demonic growths holding them together vanished, leaving the rubble to fall to the ground, once again bound by the laws of physics.

The lava likewise cooled down instantly, turning into solid rock before her very eyes. The crater remained, however; while the demons' influence was gone, their damage remained.

She flew down to meet back up with Luna and The Slayer, the latter of whom was simply walking across the now-hardened lava.

"Is... is it over?" Twilight asked.

"It would seem so," Luna answered, cautiously. "At least, in Manehattan. We do not know if the demons will try to open another portal elsewhere."

Thinking back to her earlier encounter, Twilight took a deep breath. "Also... something happened while you were fighting."

Luna tilted her head, and The Slayer ignored her as he kept walking. "What was it?" Luna asked.

"The demons... one of them talked to me."

The following silence was palpable, the only sound in the city being that made by the handful of leftover fires. This silence was then broken by semi-rapid footsteps, as The Slayer proceeded to quickly walk back towards the two ponies.

Though she could not see his face, Twilight still flinched away from what was no doubt a glare, as he stood right above her and stared down.

If Luna was concerned by his sudden proximity, she didn't show it. "And what did they say?"

Twilight found it in herself to look The Slayer in the face. "They... wanted me to reseal you. They told me that if I did, they'd leave Equestria for good."

Luna looked back and forth between them, as they stared each other down. "And what did thou decide?" she slowly asked, her magic already starting to form around the hilt of her sword, though she wasn't sure who it would be used on.

"I declined." The Slayer made no movement, but she could practically feel his gaze softening. "But it sounded like they were going to try to ask me again later."

Suddenly, The Slayer squatted down to Twilight's eye level, making her flinch back even more. Despite her fear, she still forced herself to stare him back.

Oddly enough, at this proximity, she could just barely make out the contour of a face underneath his visor, along with a pair of blue eyes...

One of The Slayer's hands moved, and Twilight instantly shut her eyes as she cowered, while Luna called out, "Stop!"

However, instead of the brutal execution she was expecting, Twilight just felt a hand pat her on the back, followed by footsteps heading away from her.

Twilight timidly opened her eyes, and she saw Luna looking just as confused as she felt.

"Did... did he just pat me on the back?"

Luna could only nod slowly.

It was a few more seconds before Twilight realized The Slayer was starting to climb out of the crater. "Wait, Mr. Slayer!"

He did not stop, so Twilight landed near the outer edge of the crater, to intercept him as he clambered up. "Where are you going?"

He gave no answer, and simply kept walking.

"Will you come with us? Equestria could still be in danger!" Twilight pushed, placing herself directly in his path.

Still no response, and he just nonchalantly walked around her.

Luna joined them. "Please, Mr. Slayer, we cannot hope to keep the demons at bay without your help!"

Evidently, he had his own plan for that, as he just continued walking away.

Twilight tried to think of a way to sway him. She knew he hated demons, but what would his end goal be?

As she thought, a few details sprang to mind:

Discord claimed that he had fought demons for "eons", and the demon had referred to him as "The Hell Walker"...

Putting the pieces together, Twilight blurted out, "We know where the entrance to Hell is!"

That made him stop, and slowly turn to face her.

Encouraged by getting any sort of response, she continued. "Not far outside of Ponyville, my hometown, there's an entrance into Tartarus. The same place the demons came from."

Luna caught onto her argument, and continued. "If we take you there, you can stop the invasion from the source, correct?"

After a moment, The Slayer nodded, and went up to them expectantly.

"Alright, so, let's just teleport there, and-"

"That will not work," Luna cut her off. "I tried to cast a few spells to assist him during our battle together. None of them took hold. I don't believe common magic is enough to penetrate his armor."

The Slayer looked at his own arm for a moment, before turning back to Twilight. She had little more than a sheepish smile to offer.

"We could... take a chariot, instead?"

Soul

City officials were asking all kinds of questions, but neither Twilight nor Luna had any satisfying answers. Thankfully, The Slayer's presence put a stop to any further lines of questioning.

A chariot was already waiting for them, pulled by a squad of four guards. They all shrunk at the sight of The Slayer, but did not run.

"I'll send a message to my sister and Discord," Luna said. "They may be able to assist."

Twilight nodded. "And I'll write ahead to Spike and the others, let them know we're coming."

While they wrote on their own parchments, The Slayer took his place in the chariot. It was surprisingly roomy, and allowed all three of them to be inside with little discomfort.

Even though she knew he was allied with them, Twilight still felt uneasy about being so close to The Slayer.

Once both their letters were flying to their destinations, Luna shouted at the guards. "Onwards! Time is of the essence!"

The guards saluted and broke into a gallop. Soon, they lifted off, leaving the ruined city of Manehattan behind them.

Seeing as Manehattan was on the other side of the mountain Canterlot was on, the trip would be even longer this time. The day was catching up to Twilight, and she caught herself nodding off.

Luna smiled at her. "Fear not, Twilight Sparkle. There is no harm in having a brief nap, if you need it. I will watch over your dreams, and make sure no demons try to sway you again."

The Slayer just looked between them, then shrugged and watched the landscape below them.

Twilight yawned and leaned against the side of the chariot. "Thank you, Luna."

She closed her eyes, and then she was asleep.

Once more unto the void.

Twilight looked around. "Luna? Are you there?"

"Very interesting."

Twilight whirled around, but the void was still empty. "Who was that?! Are you a demon, too?"

The voice laughed. "Fear not, young one. I am not one of the hellspawn."

It did sound different from the demonic voice... but not by much. "Who are you, then?"

There was a pause. "It would be best if I did not tell you. Most mortals cannot stand to know the truth. But I will tell you that I am an ally of... him."

A frozen figure of The Slayer materialized in the void, and Twilight cautiously circled around it. "How do you know The Slayer?"

"I watched as he enacted his one-man crusade against the forces of Hell. And so, I bestowed upon him enhanced abilities."

Twilight put a hoof to her chin. "So... you.... blessed him?"

The voice chuckled. "That would be the perfect word for it."

"Wait, hold on," Twilight turned away from The Slayer to speak to the void. "Why are you talking to me, then?"

"When you helped to free The Slayer from his imprisonment, you merged your consciousness with his for but a moment. It was enough to establish a small connection to me... as well as the demons."

The void turned into a burning hellscape. Twilight jumped back, but relaxed when nothing felt different. "So... you heard what happened, then?"

"Not many mortals would deny a demon's offer so readily. For that, I must commend you, Twilight Sparkle."

"Oh, well... thanks?" She shook her head. "Is that all you came here to tell me?"

"I am also here to reassure you. Since you are assisting The Slayer in his mission, I will tell you that you must close the entrance to Hell within your realm, through any means necessary."

Twilight nodded. "Close the gateway to Tartarus, easy enough."

"It will not be so simple, young one. The only way to close it will be within."

Her ears folded against her head. "Oh..."

"Fret not. It is not your world's time to give penance... So long as you remain untainted by the evils of Hell, you shall succeed."

"Yeah... I guess you're right." After a moment, Twilight whirled around. "Wait, 'my world's time'?"

She got no answer, and everything around her faded away.

Twilight awoke just as the chariot landed on a balcony of her castle. A massive purple shield was around the entire structure, with several demons attacking it at various places. Thankfully, it held strong.

Luna nodded at her. "I hope your nap was nice. I can confirm that no demonic presence appeared while you were asleep."

Twilight sighed in relief. That voice was telling the truth, then. She was about to tell Luna about it, but decided against it. The last thing she needs right now is to worry about some other group of beings, even if they are allied with The Slayer.

Speaking of him, he was already waiting on the balcony. He probably hopped off before the chariot fully landed.

As soon as the princesses stepped off the chariot, the castle doors blew open, and a pink blur grabbed them both into a crushing hug.

"I was so, so, sooooo worried!" said a crying Pinkie Pie. "Thank Celestia you two are okay!!!"

The Slayer reached for his shotgun when they were bowled over, but sheepishly put it back once he saw what was happening.

"P-Pinkie, can't...! Breathe...!"

"Oh, whoops!" Pinkie immediately stopped crying and let them both go. "Sorry about that."

Luna inhaled deeply. "Glad to see you are also okay, Pinkie Pie."

Back at the door, the rest of Twilight's friends stepped forward. They all looked pretty haggard, but still happy to see their friend again.

"So nice to see you again!" Rarity said as she hugged Twilight. The others quickly joined in.

"Thank you girls," Twilight said. "How's everypony else doing?"

Starlight disengaged from the hug. "No one's seriously hurt, thank the stars, but we had a lot of panic. They're only just now starting to calm down, since I told them you and Luna were coming." She shot a sideways glance at The Slayer. "No idea how they'll react to him, though."

"Yeah, what is he, exactly?" Dash asked, flying closer to him. "All you said was he's powerful and on our side."

Twilight gulped. "It's... a very long story. For now, all that matters is that he'll help us get rid of the demons. Right, Mr. Slayer?"

He looked at her, and nodded.

Dash orbited around him, and he followed perfectly. "I dunno, that armor is cool and all, but I don't see how he could do that much."

Applejack walked up. "Dash, this feller is covered head to toe in blood. Since Twi here is vouchin' for him, Ah'm pretty sure that's demon blood."

Dash looked him up and down. "Oh. Ew."

Fluttershy leaned closer to Twilight. "Is it alright if we go back inside, now? The animals get so worried when I'm away for too long, and I don't want Angel Bunny to do anything rash."

Out of the corner of her eye, Twilight noticed The Slayer perk up slightly at the word "bunny." "Yeah, we should go inside."

The guards dismounted the chariot and followed behind Luna in formation as they all entered the castle. The halls contained the odd group of ponies lying down on blankets, caught up in various activities. Some were trying to sleep, some were comforting loved ones, and some were trying to eat a small meal.

All of them stopped when the group entered, and they reflexively gave small bows to Twilight and Luna. They then all froze when they spotted The Slayer, but no one said a word.

Starlight led them to the cutie map room. There, Spike and Trixie were seated, both looking uncharacteristically grim. Behind them, a group of animals were laying around, looking nervous.

Both of them brightened when they saw Twilight, however. "Twilight!" they both shouted in unison.

"Hey, Spike, Trixie-" Twilight was cut off as she was surprised with another group hug.

Trixie broke off first. "Trixie is glad you're safe."

"Yeah, it's been a nightmare here," Spike said. "Thankfully we got the town into the castle fast enough. Starlight and Trixie were able to make a great shield spell, too!"

Starlight blushed at the praise, while Trixie smiled.

At the back of the room, Fluttershy giggled as she was assaulted with her own group of hugs. "Now, now, settle down, you guys."

Twilight noticed too late that The Slayer was walking towards the pegasus and her animal friends. "Uh, Fluttershy?"

"Yes, Twili- eep!" Fluttershy froze when she saw how close The Slayer was, and the animals did the same.

All except for a lone white rabbit, who took a defensive stance in front of her.

The Slayer and Angel stared each other down for a moment, before the former knelt down and reached out a hand.

Angel seemed to take it as a threat, and he immediately hopped onto the hand and started trying to bite it.

The Slayer just stayed in position as Angel "attacked" him. After a moment, Fluttershy realized what was happening.

"Angel, no!"

The rabbit paused mid-bite, then looked at her, still sitting on The Slayer's hand.

Before either of them could do anything, he brought his other hand to Angel's head, and gently scratched a finger against it.

Angel stiffened at first at the contact, then slowly leaned into it. He still frowned aggressively at Fluttershy, but she could tell it was just an act.

While Fluttershy giggled at their antics, Luna cleared her throat. "We still have business to attend to."

Twilight nodded. "Did you get a response from Celestia and Discord?"

"Yes, while you were asleep. They should be here in a little while."

"Should we wait for them?" Starlight asked.

"That sounds like a good idea to me," Dash said. "That robot over there might be tough, but having an extra princess here would help, not to mention Discord."

Twilight tilted her head. "Robot?"

"Yeah, look at him!" Dash pointed at The Slayer, who was still petting Angel. The rabbit had given up his facade and basked in the petting. "All that futuristic armor, I bet there's nothing underneath but gears and sparks."

"Now why would a robot play with a rabbit?" Applejack asked. "Fer that matter, why is he doing that, anyway?"

Twilight thought back to the pet store and winced. "He seems to be... fond of rabbits."

The group was silent for a moment, until Dash shouted across the room, "Hey, Slayer dude! Take off your helmet!"

The Slayer froze, and looked at her. Dash's bravado melted instantly. "Y-you know, so we can make sure you're not... uh..."

"A demon!" Pinkie chimed in.

"Yeah, that!" Dash said. She slipped a quick hoof bump to Pinkie afterwards.

Luna stepped forward. "I am a bit curious, myself."

With all eyes on him, The Slayer slumped slightly, and gently deposited Angel back on the ground. He then stood back up and walked toward the ponies.

He looked back and forth at them, and when none of them backed down, he slowly brought a hand up to his helmet.

There was a click, and a hiss of air. Then he grabbed the helmet and slowly pulled it up.

Twilight wasn't sure what she was expecting. Even though The Slayer was a creature unlike any she had seen, he still looked... normal.

He had short black hair on his head, and his blue eyes held a piercing gaze. His face was rugged, as if it had seen a million battles in his lifetime. His expression was the very definition of neutral, though it leaned towards a slight frown.

"...huh," Dash said after a while. "Well, not a robot, then."

The Slayer rolled his eyes and replaced the helmet. There was another hiss, and then he was the same faceless golem as before.

"Anyway," Luna said, "we've wasted enough time. We should go over the plan."

Twilight nodded and used her magic on the cutie map to project an image of the land around Ponyville. She pointed to a spot within the Everfree Forest. "The opening to Tartarus is out here, in the base of a small mountain. I believe that, if we can seal it off, then we can stop the invasion for good. First, we'll-"

Twilight was interrupted by a crash, and she looked up just in time to see the doors swinging shut. Another look around the room revealed that The Slayer was now missing.

"Awful rude of him," Trixie commented. "What is his problem?"

Twilight facehooved. "He's not waiting for plans, and is going to handle it himself. I should've expected this."

Luna put a hoof on her shoulder. "We should try and keep up with him, then."

"...yeah, we should." Twilight turned to the others. "Everypony, stay here and watch after the citizens. When Celestia and Discord get here, tell them where we're going."

Pinkie saluted. "Aye aye, Princess!"

"Wait, you're going back out there?" Fluttershy asked. "We should help you!"

Twilight sighed. "I'm sorry, girls, this isn't a problem that friendship can solve. I need you all to do your part here. I released The Slayer in the first place, so... I need to see this through."

They shared some sad looks, before Rarity lunged forward and hugged her. "Just come back in one piece, okay, darling?"

The others joined in for another group hug, sharing similar sentiments.

"Thanks, girls." Twilight smiled. "I promise I'll come back."

Outside, they could hear muffled explosions and demonic screeches.

"Come now, Twilight," Luna said, adjusting her armor. "We shouldn't fall too far behind."

With one last farewell, Twilight left her friends behind, and headed to her mission.

Fortress

Author's Note

I missed my deadline to finish this before Eternal came out, but oh well.

Fortress

Just like in Manehattan, it was incredibly easy to follow The Slayer. His path of carnage through the assorted demons was unmistakable.

In fact, while Ponyville was most definitely under attack, there were far few demons than there had been in Manehattan. This meant that The Slayer was able to blaze through them, making a beeline for the treeline of the Everfree Forest.

The forest was far from untouched. Several fires raged through the woods, and the air was thick with the sounds of fleeing animals and rampaging demons. Twilight hoped that Fluttershy didn't hear too much about what happened...

Luna landed and galloped behind The Slayer, expertly weaving over and around the trees. Twilight did the same, but found herself stumbling more often.

Soon, the obstacles cleared, but were replaced by the ground becoming fractured in various places. Despite this, Twilight was able to clear the distance with the elder princess. "So he's going to the entrance to Tartarus, right?"

Luna absentmindedly swung her sword at a demon that was left dazed by The Slayer's attack, cleanly decapitating it. "I would hope so. Still, given the state of these woods, we might have to take a detour by our old castle."

"But does he know that?"

Luna did not answer.

The Slayer stopped just long enough to jump up and chainsaw a flying demon in mid-air. The creature screamed, its two halves falling to the ground just before The Slayer did.

With his breakneck pace now paused, he seemed to notice that the path they were taking now led directly into a gorge, which was also burning. The mountain that housed the entrance to Tartarus was on the other side.

The Slayer looked like he was contemplating jumping down, so Twilight called out. "Wait, Slayer!"

He paused, and looked at her.

She skidded to a stop in front of him, Luna right behind her. "There's an old castle nearby, with a bridge. We can get across there, and make our way to the gate."

He nodded. Twilight galloped by the edge of the ravine, keeping her eyes peeled for the bridge through the remaining trees and the smoke. Luna and The Slayer followed closely.

Soon, she found the bridge. Or, rather, what was left of it. The demons' rampage left it entirely destroyed, the stakes in the ground at either end being the only remaining sign that there was a bridge at all.

Still, this provided the smallest gap across the gorge for them. Twilight turned to The Slayer and Luna. "Okay, we'll have to... carry you across. Is that-"

The Slayer ignored her, and took a running jump across the chasm. The jump was far longer than she was expecting, and The Slayer managed to grab the other cliffside and haul himself up.

"...or you could do that," Twilight said.

Luna couldn't suppress a small chuckle. "We should have seen that coming."

The two of them flew over. The ruins of the old capital of Equestria stood tall, albeit a bit more damaged than before. Curiously, there were no demons in the immediate area, but that didn't rule out inside the castle.

"Alright, it should be just on the other side of the castle," Twilight said. "From there, it's basically a straight shot to Tartarus."

The Slayer nodded and led them again. However, when they got close to the castle, he suddenly stopped and looked at it.

Twilight wasn't expecting the sudden stop, and almost ran right into his back. "Is something wrong?"

Like always, he didn't answer, and walked towards the castle wall. This was the first time they saw him like this, and it was worrying.

"Does he sense something inside the castle?" Luna asked.

"Why would he have interest in our old home?"

Luna and Twilight looked up just in time to see an armored Celestia land by them. She was slightly covered in blood, but her expression made it clear that none of it was hers.

Luna smiled and shared a brief hug with her. "Glad to see you are alright, sister."

Celestia smiled. "Same to you, Luna." She turned back to The Slayer, who was poking around the wall. "What is he doing?"

"We're not sure," Twilight said. After a moment, she asked, "Wait, where's Discord?"

"Right here."

Twilight jumped and whirled around to find Discord lounging in the air. "Don't do that, we're in the middle of an attack!"

Discord smirked. "Oh, sorry, Twilight, but you know that someone around here has to try and keep spirits up."

The Slayer shot a very noticeable glare at Discord upon his arrival, and held a hand dangerously close to his weapon. Discord returned the murderous gaze with a smile. "Oh, don't worry, Slayer," Discord said, "I'm not one of those demons. I'm with the good guys this time."

The ponies nodded in agreement, and The Slayer slowly brought his hand away from his gun. After another moment, he looked at the wall, nodded in satisfaction, and then punched a certain spot with all his might.

The hole revealed a hidden passage that led underground, and he quickly hopped into it.

The ponies were perplexed. "What exactly does he hope to find in there?" Celestia asked.

"I have no idea, sister," Luna said. "But we should probably follow him."

"Do you two not know what lurks below your own castle?" Discord asked, his voice being sincere for once.

Luna used her horn to light the darkness within the passage as she dropped down. "We do, but we know not what The Slayer could be after."

Celestia and Twilight followed her inside. Discord shrugged and slithered after them.

The stairs led downward for quite some time. Soon, Twilight noticed that there was a curve to the descent, meaning they were spiraling further into the ground.

"So... what's down here?" she asked after a moment.

"In the past, treasure and dungeons," Celestia said. "Before..." She gave an apologetic glance at Luna. "Before I left this castle for Canterlot, we had converted it into the original lab and storehouse for our scholars. The same ones that Observable Aegis is a part of."

Twilight tilted her head. "Is The Slayer looking for something that was left down here?"

"That can't be," Celestia answered. "We emptied out this location when we moved labs." Suddenly, her frown deepened. "Unless..."

"As I understand it, there was one artifact that was too large to be moved at the time," Luna said. "We normally sent squads regularly to confirm its condition. According to the records, nothing has changed in all this time."

Discord tapped his claws together as he floated alongside them. "And what was this artifact? I didn't think to dig around your old castle the last time I broke free."

The interior wall of the staircase opened up into a large cavern. Several rows of empty cases and shelves were carved out of rock on the floor below, lit up by magical lanterns that popped back to life at their motion.

The Slayer was far ahead of them, so the three opted to fly straight down instead.

"It was a structure of unknown origin that was buried in the ground beneath the castle," Luna explained. "It was the first artifact we discovered during our rule, and was the reason we founded our group of secret scholars in the first place. To find a way inside."

The lights continued to turn on, until they revealed what looked like another castle, partially buried in the stone. While it looked older than the castle above it, Twilight could see what looked like large, modern glass windows lining a section higher on its wall. Below that, there was an indentation that looked like an entry, surrounded by countless scars and imperfections.

"You mean you never opened it?" Discord asked.

"Nothing we tried could open it, or even damage it in any significant way," Celestia said. "We were even unable to teleport inside. Whatever it is, it's able to suppress magic that attempts to intrude upon it."

Discord snapped his fingers, and nothing happened. He snapped a couple more times, then gave a low whistle. "It even blocks chaos magic. How unusual."

The three of them assembled at the door. "Is this what The Slayer was looking for?" Twilight asked.

Luna looked back at him just as he decided to follow their approach and fall the rest of the way. "It is possible. Though I am unsure that even he will be able to gain access."

The Slayer dusted himself off, then strode towards them. They parted and allowed him to stand right in front of the supposed entry to the building.

Twilight leaned around him to try and see what he was doing. To her shock, one of the red lights on his suit flickered to blue for a moment, and the door slowly hissed open.

The princesses' jaws dropped. Discord's jaw actually left his face and hit the ground with the sound of shattering glass.

Unperturbed, The Slayer entered.

Luna was the first to recover, and followed him inside. "What is the meaning of this?!"

Celestia shook her head and went after her. "Just who is The Slayer?"

Discord swept up his broken jaw and reattached it, then jabbed Twilight in the ribs with an elbow. "Come on, we should go inside."

He glided in, and Twilight galloped after. "Hey, wait!"

Once she was inside, the door hissed closed behind her.

The inside was pitch black, so Twilight lit her horn. She was able to find Discord and the princesses easily enough, since this appeared to be a narrow passage with only one path. Curiously, despite the ancient-styled exterior, the inside was made of smooth metal. It looked downright futuristic.

The Slayer was at the front of the group, and for once showed no haste in his movement. In fact, his head was down slightly, unusual from the way he normally kept it up and scanning for threats.

Soon, the passage ended at a set of steep stairs leading to a hatch. The Slayer ascended and swung the hatch open, and the others followed.

The room they emerged into looked like the bridge of a ship, and Twilight could see the cavern they just left out of the giant window lining the wall behind the consoles. The ambient light allowed them to see, but there was still no light at all coming from inside.

The Slayer walked deeper inside the building, until he was lost in the darkness. Twilight was about to call after him, but there was a sudden noise, like something powering up.

Soon after, interior lights came on, revealing that the building was made out of that futuristic metal, but styled to look like it was wooden. The Slayer was standing in front of a bright blue pillar of energy, which pulsed and spread that same blue glow across barely-visible circuits in the walls, ceiling, and floors.

Celestia was agape. "This... is what we were living above all this time? How old is this?"

Luna was equally bewildered. "Slayer, how are you connected to this?"

The Slayer did not answer, and instead walked past them to the consoles. He tried to press one of the screens, but it turned red at his touch, and displayed a message in a language that Twilight couldn't read.

She walked over out of curiosity. "Is something wrong with this... place?"

The Slayer gave a small nod, then reached into a compartment on his suit. He pulled out a small device, barely bigger than the tip of his thumb, and plugged it into the console.

The screen turned blue and a progress bar started to fill up. When it was complete, it offered a prompt, and The Slayer pressed one of the options.

The lights flickered, and the screens flicked off before coming back on, now displaying an odd circular emblem.

Another progress bar filled up, and once it was done, the screens returned to their previous state, displaying unreadable messages in blue.

Suddenly, a disembodied voice spoke throughout the chamber. "Restoration complete. Hello again, Slayer."

Twilight and the princesses whirled around, looking for the source of the voice. Discord looked equally confused, but was taking glee in that fact.

"Who was that?!" Twilight asked. "Where are they?"

"My memory banks contain a large gap between my deactivation and now," the voice continued. "Would you like me to analyze your suit recordings in order to brief myself?"

The Slayer nodded at the screen he was looking at.

"Very well. Accessing Praetor suit video logs..."

Another progress bar filled up on the screen. When Twilight looked closely, she could even see a similar bar working within The Slayer's visor.

Once the bar was done, the voice spoke again. "Analyzing complete. I am now fully versed in the current situation."

The Slayer turned to the confused ponies and chaos god.

"Greetings, guests," the voice said. "I am VEGA, an artificial intelligence formerly in charge of the UAC Mars base. Due to prior events, I am now assisting The Slayer on his mission."

Luna looked around the room. "And... what would that mission be?"

"The complete and total eradication of Hell and its demons."

"Wait, what prior events?" Twilight asked. "What's the UAC? Mars? What is this place?!"

"I'm afraid we do not have the time for a full explanation, Twilight Sparkle," VEGA responded. "For now, all that matters is that this is a different dimension than our own. This ship was of Night Sentinel design, and the Doom Slayer was formerly a member of their ranks."

"Night Sentinels?" Luna asked. "And The Slayer was...?"

Her questions went unanswered. "Slayer, there is an upgrade to your Praetor suit in storage within the ship. It is the only weapon left in the armory. Would you like me to install it?"

The Slayer nodded. A section of the floor raised and opened up an arm-size protrusion, which he filled quickly. There was the sound of whirring machinery, and then he retracted his arm, and the floor lowered again.

The Slayer's left arm was now sporting a wrist blade. However, when he flexed his arm and extended it, the length rivaled that of a normal sword. He seemed satisfied, and retracted the blade.

"The ship's power levels are low, but I can draw energy from the ground and air around us," VEGA said. "By the time you are done with your mission here, I should have most of the ship's primary functions active, and then we can use this to save Earth."

The Slayer seemed hesitant for a moment, so VEGA continued. "Initial readings show that this realm is similar to Hell because of how it warps time in relation to other realms. Though you were trapped here for over a millennium, only a few years will have passed in our own dimension."

"Cross-dimensional beings, eh?" Discord said. "Quite unexpected, but I like it."

"VEGA," Celestia said, "do you know if our world will remain safe from the demons after we close the portal here?"

"Once the primary Hell entrance is closed, demonic activity should cease almost entirely. After that, it will be up to you to ensure that another portal is not opened, at all costs."

"Then we should get moving," Luna said. "The sooner we leave from here, the sooner we can stop this attack." She started to open the hatch they came through, but VEGA interrupted her.

"That will not be necessary, Princess Luna. I have just enough power now to send you all much closer to the Hell portal. Once the job is done, I will have enough to open a portal for The Slayer to return."

The consoles shifted to the sides of the platform as a set of pylons arranged themselves into a ring in front of the giant window. A walkway also rose out of the floor, and a moment later a bright blue portal formed inside the ring.

"I cannot maintain the portal for long."

The Slayer waved everyone forward, then jumped through. Discord was the next to enter, giggling like a child all the while. Celestia and Luna nodded at each other, then walked through the blue abyss.

Just before Twilight stepped through, she turned around and asked, "VEGA... is this invasion my fault?"

"Judging by recordings from The Slayer's suit, the demons are probably trying to guilt you into assisting them. You were wise to decline, not only because they would betray you, but because The Slayer would not hesitate to kill you if you had sided with the demons."

Twilight shuddered. "Thanks... I think?"

"Please, enter the portal."

"Right, yeah, sorry." She looked back at the portal. "VEGA... will we meet again?"

"Once The Slayer is done here, hopefully you will never have to encounter either of us again."

Twilight took a deep breath, and jumped through the portal.

Doom

Twilight emerged from the portal in front of a large cavern opening. Celestia, Luna, and Discord were already waiting for her, while the Slayer was already walking inside.

Just before the portal closed behind her, a small drone flew out and hovered in front of the group. "I will be remotely piloting this drone to provide limited assistance," VEGA said from it.

"Just how much technology was hidden in that ship?" Luna asked.

"A full inventory was completed shortly after I was reactivated. However, I am unable to perform a full scan until power is fully restored."

"I think that was- Nevermind," Celestia said. She looked at The Slayer, who was now quite far into the cave. "We should get moving if we wish to keep up."

The others nodded and they hurried over to him. VEGA's drone flew alongside them. The Slayer gave it a glance when they arrived, but didn't pay it a second look.

"Because this is a natural Hell portal, closing it off will take more work than usual," VEGA said. "When The Slayer has finished his end of the work, you need to use your magic to complete the seal from your side."

"Oh, is that all?" Discord said. "And here I thought closing off access to an entirely hostile dimension would be more complicated."

VEGA didn't respond to the quip.

Discord pouted. "Oh, robots are no fun. They never get sarcasm."

"I understood the attempt at humor, Discord, I simply saw no need to acknowledge it."

"...oh."

"Enough talking," Luna said while unsheathing her sword. "Expect resistance soon."

The darkness of the cave was slowly replaced with the violent orange glow of Hell. The gates that were normally guarded by Cerberus were wide open, and the guard dog was nowhere to be seen.

The Slayer strode directly into the Tartarus gates and beelined toward a single idle imp. It barely had the time to screech before The Slayer tried out his new arm blade on it. He stabbed it through the abdomen, then pulled it up, leaving the demon's top half to flop apart on the ground.

The Slayer inspected the blade and retracted it. He seemed quite pleased with the results.

He didn't get to sit in satisfaction for long, because soon after a horde of demons of all shapes and sizes hissed and screeched from deeper within Hell. They crawled out from just about every pit and crevice in view, with a few simply teleporting in with a flash of red lightning.

The Slayer made sure his shotgun was loaded, then jumped into the fray. VEGA's drone followed above him, likely to provide combat support.

Celestia winced at the display of violence, while Discord went wide-eyed. Twilight and Luna were numb to the carnage by now, so they instead looked around them.

"So that's what he's like in action," Discord said. "Pretty glad I never pissed him off, then."

"Come," Luna said, "we should look for a way to close their access to Equestria while he distracts them."

Everyone nodded in agreement and searched the area, trying to ignore the deafening slaughter not too far away from them. A few stray demons tried to attack the group, but they were easily dispatched by Celestia and Luna's swords.

Meanwhile, Twilight kept intermittently pulsing magic from her horn, trying to look for any sort of weak point in the connection between worlds. Unfortunately, it was as if the very air in Hell was charged with magic. It would no doubt be helpful if one of them had to cast a strenuous spell, but it made locating a way to sever the realms impossible.

The others had reached the same conclusion, judging by their disappointed faces.

"Do you think it's like it was at Manehattan?" Twilight asked Luna.

"It is possible," Luna said. "However, in a realm such as this, a pillar of flesh could very easily blend in."

"Our big green friend is getting farther away," Discord reported, hovering above them. "It might be in our best interests to turn back so we don't get too far."

"That would be wise," Celestia said. "Come, Twilight."

"Oh, but my guests just got here."

Everyone whirled around, blades and magic at the ready, and were met by a bipedal figure, similar to The Slayer in stature, but without any armor save for an ornate crown and clutching a staff. However, his glowing red eyes betrayed his demonic nature, as well as his sickly gray skin.

"Who are you?" Luna demanded. "Tell us at once!"

"I'm afraid you don't get to ask questions here," the figure said. He chanted something under his breath and tapped his staff on the ground, and suddenly the four of them were engulfed in red lightning. They all screamed in pain and fell to the ground, along with the princesses' weapons.

"So arrogant, thinking you can free The Slayer, bring him right back into Hell, and still get to ask questions." The demon smiled cruelly. "Especially you, Twilight Sparkle."

Twilight grit her teeth and looked at the figure.

"You know, what's going to happen to your world is your own fault. If only you accepted our offer and kept The Slayer contained, no more souls would have to be collected." He chuckled. "Well, now you get to suffer for your mistake firsthand."

The lightning intensified, and everyone screamed again. Even still, Twilight found it in herself to glare at the demon and say, "He... will stop... you!"

The figure frowned. "Still so arrogant. I see The Slayer has rubbed off on you a bit. Well, we can-"

He suddenly looked up, and his eyes went wide. He brought up the staff and teleported away just before a bright blue beam tore through the space he once occupied.

The lightning holding them in place with pain persisted, however, and while it was less painful now, it still held them to the ground. The figure reappeared on top of a distant rock. The Slayer ran past them and once again took aim with his laser weapon.

"Slayer!" the figure growled out. "Take one more step towards me, and their souls are forfeit!"

For the first time since Twilight had seen him, The Slayer hesitated. He kept his weapon ready, but did not run forward, nor did he fire.

VEGA's drone flew in shortly after and inspected the immobilized ponies and chaos god. "He is using Argent energy to keep you all in place."

"Who... is he?" Celestia forced out. She tried to rise to her hooves, but yelped and fell back down as the lightning intensified for a moment.

"That is Deag Nilox, a Hell Priest. It would seem he is in charge of attacking Equestria."

Deag Nilox growled. "I have a proposition for you, Slayer!" he shouted. "This world will suit our needs just as well as Earth! If you allow us to take it, Earth will be spared its fate!"

The Slayer took one look at the imprisoned beings around him, then glared right back at Nilox. He put away his gun, but then cracked his knuckles.

Nilox scowled. "Then their death is on your hands!"

He banged his staff on the ground, and everyone screamed as the lightning intensified again.

The Slayer looked truly conflicted, which was very unusual for him.

Even through the pain, Twilight did her best to focus. She forced her eyes open and looked at Nilox. She just had to manage...!

With a scream and a sudden nosebleed, Twilight used her magic to levitate Nilox's staff. The force surprised him, and it was violently wrenched from his grasp, flying far into the Hellish abyss.

The lightning around everyone instantly dissipated, and The Slayer took off towards Nilox. However, he still did not pull out a weapon. It appeared he made one decision already.

VEGA's drone flew above the group and dispatched a light blue gas. As everyone breathed it in, they slowly felt better, until they could all stand up again.

Twilight wiped the blood off her muzzle and stood up. "What was that?"

"A nanobot cluster, intended to provide immediate healing from your injuries," VEGA explained. "Though your species is unlike any sentient life in my records, the fundamentals are still close enough to humans to assist."

Shortly before The Slayer could reach Nilox, the priest teleported away again.

"Wretched fools!" his voice echoed around them. "I have no more time to waste on you. My new pet shall deal with you now."

A massive red portal opened, and Cerberus jumped through. He was definitely bigger than Twilight remembered him, though, and each head was mutated into a far more demonic visage. All three heads roared, and The Slayer prepared his rocket launcher.

At the same time, other demons screeched from behind Twilight and the others, and they scrambled to get ready for combat.

"Should any of us help The Slayer?" Twilight asked.

"I think he can handle himself," Luna said. Before any more words could be said, she let out a battle cry and lunged at the nearest demon. Her sword impaled its head, and she quickly jumped to the next target.

Celestia's fighting style was much more defensive. She'd wait for a demon to attack her before she expertly avoided the blow and responded with her own lethal strike.

Discord, in the meantime, was much less concerned about the fight at first glance. He hovered a good distance above the main fight, lounging on thin air. Any fireballs heading towards him simply ricocheted away, as if they were a rubber ball. Any flying demons that got too close were instantly and inexplicably smashed back down to the ground by an assortment of random large objects.

Twilight stuck close to Celestia and fired blasts of magic at the demons. Her attacks were much less bloody than the others, but they still dropped hellspawn all the same. In the back of her mind, Twilight knew that she shouldn't feel this comfortable killing living things, but she pushed the thoughts aside for the moment. All of the bloodshed she had witnessed in the last several hours had hardened her nerves on the matter, though she still teleported out of the way the instant a demon got too close for comfort.

The horde thinned out slightly, so she took the time to look over at The Slayer. Cerberus's left head was an icy stump, and Twilight briefly wondered how The Slayer had already taken care of one of the heads. The center head breathed a massive stream of fire, while the other barked out lightning bolts. The Slayer dodged all of it with ease, running circles around the giant canine while peppering it with bullets.

It wasn't long before the last of the demons in their immediate area was killed, and Luna looked around the pile of bodies around them. "Sister, have you seen my sword?"

"I believe you threw it into one of the giant red floating demons," Celestia said. "I didn't see where it landed."

"You mean this sword?" Discord asked, pulling it out of a top hat with a flourish. Luna simply levitated it back into her sheathe, unamused.

The Slayer jumped on Cerberus's back and used his arm blade to stay in place. He pulled out his shotgun with his other arm and fired both barrels into the lightning-spewing head, causing it to fly apart into sparking pieces of meat. The lone remaining head howled and bucked The Slayer off.

"Told you he had it handled," Discord said, floating next to Twilight.

Celestia walked to the other side of her. "Then we should resume looking for a way to sever our worlds."

"That will be unnecessary," VEGA cut in. "Scans indicate that Deag Nilox was using Cerberus as the main catalyst for widening the rift between Equestria and Hell. When Cerberus is dead, the connection will return to the strength it had before the invasion."

"And then we can seal it for good," Twilight said. "Right?"

Celestia sighed. "It will take a great deal of magic from all of us, and we will lose a reliable way to seal especially dangerous villains away, but..." She looked at the bodies around her. "...that would be better than the alternative."

The Slayer fired a barrage of rockets at Cerberus, and blew off one of its legs. This appeared to metaphorically take the fight out of it, and it simply lay on the ground while The Slayer approached slowly.

"We may want to get behind something," Discord said, pulling out a barrel of umbrellas. "I get the feeling we're in the splash zone."

Celestia raised an eyebrow. "At this distance?"

Twilight and Luna knew better, so they accepted an umbrella from Discord.

The Slayer reached Cerberus's remaining head. He pulled out he massive weapon he used in Manehattan, jammed it into the beast's mouth, and pulled the trigger.

The weapon caused a bright green glow in Cerberus's head, before the entire creature exploded into a green-sparking pile of gore. Luna, Discord, and Twilight deployed their umbrellas. Celestia was unfortunately the only one to get drenched in quite a lot of blood.

She just stared ahead, unamused, and cast a cleaning spell on herself. "Oh. I see."

With no more demons in the area, The Slayer walked over to the others.

"The portal is now returning to its previous size," VEGA reported. "Demonic activity in the area has also decreased significantly."

"Then we shall begin sealing the entrance to Tartarus," Luna said. She took flight back to the entrance, Celestia close behind. Discord lingered for a bit, then snapped his fingers and popped back with them. However, Twilight remained for a bit, watching the being that helped save their world.

The Slayer, meanwhile, simply looked at the drone.

"Deag Nilox's location is currently unknown. Judging by what he said earlier, he has likely returned to assist with the demonic invasion of Earth. The Sentinel ship has been recharged enough to bring you back and then teleport the ship into Earth's orbit."

The Slayer nodded.

"Opening the portal now."

A large blue portal opened in thin air, exactly like the one VEGA had opened for them before. The Slayer turned around to walk into it, but Twilight raised a hoof.

"Wait, Slayer!"

The Slayer stopped, and turned slightly to look at her.

She bowed her head. "Thank you. For everything."

He nodded, and walked through the portal.

Twilight thought that VEGA's drone would follow him through immediately, but first it went to Twilight and dropped an object on the ground. It looked like a blue piece of glass surrounded by a gray frame.

"After Equestria is disconnected from Hell, please read this in private," VEGA explained. "I was told to deliver it to you."

"Wait, what?" Twilight picked the object up in her magic. "What is-?"

The drone ignored her and flew back through the portal. It closed shortly after.

Twilight looked at the object, dumbfounded. What was it, and why did VEGA want her to read it? And why in private?

"Twilight!"

Celestia's voice snapped her out of her thoughts, and she hastily put a cloak spell on the object before tucking it into her mane. "Coming!"

She flew back to the gate of Tartarus. After some preparation, she fired up her horn along with Celestia and Luna and focused all their magic on the gate. Discord also lent his own magic, but looked nonchalant about it.

After a moment, the gate closed, followed by the earth itself moving to seal the cavern. The four of them slowly backed out of the cave, followed by the rising ground. Every so often, a seal appeared on the ground beneath them, only to join the growing barrier between them and Hell.

Once they were back in the open, one last seal appeared and the cave shut itself completely. All three ponies powered down their horns and let out a deep breath, while Discord stretched.

"So... it's over?" Twilight asked.

Celestia nodded. "I pray that it is."

They returned to Ponyville quickly, but not before confirming that the ship underneath the castle in the Everfree was no longer there. Sure enough, there was no trace of any live demons left in the land, either. The bodies of those that were slain remained, though, and they knew that they'd have their hooves full for a while with cleanup, to say nothing of the trauma of all their citizens that survived.

After they returned to Twilight's castle, and she had a heartfelt reunion with her friends, Celestia and Luna went back to Canterlot, to begin the rebuilding effort there. Discord stuck around, mainly to talk to Fluttershy about everything that happened.

Soon, Twilight's friends slowly left, to do their part to rebuild Ponyville. Twilight was going to help too, of course, but everyone was happy to let her rest for a while given everything that she went through.

Once she was in her bedroom and alone, she undid the cloak spell on the object VEGA gave her and held it in her hooves. He said to read it, but it was just a clear piece of blue glass, from the look of it. Clearly, it was some sort of futuristic tech, just like the rest of that ship was, Twilight just had to figure out how to activate it.

She scanned it with her magic, and got no result. She tried to look at it closer, but there was still no result. It wasn't until she tapped the surface of the glass with a hoof that it began glowing, and text appeared on the glass. After confirming that she could use her hoof to scroll and reveal more, Twilight studied what the artificial intelligence wanted her to see so badly.

Twilight Sparkle, if you are reading this, then The Slayer was successful in helping you close off Hell's access to your world, and VEGA was able to deliver this message discretely.

I am sure you have several questions right now. VEGA contacted me shortly after he was reactivated, and I gave him this message to deliver to you after the situation was explained.

I am Doctor Samuel Hayden, former head of the Union Aerospace Corporation on Mars. I was the one who sent The Slayer to your world, but only because I needed to in order to ensure that my plans would not be affected by his... actions.

I know you've seen how he operates. How he feels about Hell and its demons, how he fights. All you need to know about that is that I'm the one who made him that way, long ago, and he is vital to my plans here. I admit, I did not expect him to be trapped by your princesses for so long, but his return will still fit into what I am going to do.

And yes, that means I am the one who talked to you about denying the demons. There is much more to the story you do not know, but you do not need to know any more.

Twilight Sparkle, as you already know, your world is not alone in the multiverse. However, your world, as it stands, plays no part in our plan for all of Creation. Your encounter with Hell was an unfortunate one, but it is still good to know that you were able to survive it.

Tell no one else about this message. I am telling all of this to you because I know that you will understand. When my plan is complete, and The Father is returned, every realm will be safe from the demons, including yours.

That will be all. Destroy this device once you are done reading it. After five hours, it will corrupt itself, and be unreadable to anyone.

Twilight sat in her room and kept reading and re-reading the message until the message corrupted, just like it said it would. When it did, she looked up to see that it was already night time.

She numbly walked onto her balcony and looked up at the stars.

That... was a lot to take in. Especially after everything that happened.

Something was going on that could affect "all of Creation" and Equestria didn't even factor into it. Everything that happened here was incidental. Even though they had survived Hell, nothing would have changed on a cosmic scale if they hadn't.

Still... The Slayer didn't throw Equestria away for the sake of his own world. He didn't even sacrifice the lives of others to secure Equestria's safety. Underneath all the anger and hatred, there was a genuinely kind heart.

Wherever The Slayer was now, whatever he was doing... Twilight hoped that he'd save every other world he came into, just like he did for hers.

The Slayer took a rest for the first time in millennia. The ship had to reboot after the teleportation from Equestria, so he could do nothing but wait for VEGA to come back online to activate the portal so he could start saving Earth.

Through the ship's viewport in front of him, he could see rivers of lava and smoke streaking the planet. It made his blood boil, but he couldn't do anything about it yet.

To pass the time, he went through his suit's recordings of his time in Equestria. While flipping through, he stopped on one particular moment.

When he was playing with the yellow pony's rabbit.

He wanted to smile, but a memory turned it into a scowl. He saved an image of the rabbit from the recording and put it in a folder along with the only other photo he had saved on the suit.

It was an image of him holding a picture. The picture was of a fuzzy brown rabbit looking at the camera.

The Slayer clenched his fist while looking at the two images. He dismissed the displays and looked back at the ruined Earth.

He knew why he fought, and why he'd never stop fighting.

And no one will get in his way.

Author's Note

Well, I finally finished it, long after I promised I would.

And, just like I said in my blog post, this will be the last batch of words I ever write for Fimfiction. It's been a great ride, with its own ups and downs, but it's time I move on. I won't disappear completely from the site, but I am definitely done writing here.

Hope you all had just as much fun reading as I did writing. So long, and thanks for all the horses.

Unleashed

Twilight got a few odd looks from guards and maids as she sprinted through the halls of Canterlot castle, but they didn't make any move to stop or question her.

This suited her just fine. She wanted to get to The Slayer as fast as she could.

Apparently, Celestia already saw fit to give her access to the labs under the castle, because she was able to get onto the elevator without any issue. As soon as it reached its destination, she started briskly walking down the path she remembered taking the day before. She briefly noticed that a few scientist and guards gave her small bows as she passed, but she paid them no mind.

Once she was outside The Slayer's chamber, Twilight heard a voice behind her. "Princess Twilight?"

She turned to see Aegis, caught in the middle of heading to another section of the labs, judging by the clipboard being held in her magic. "What's the occasion? Didn't think you'd come back so early."

Twilight couldn't bring herself to match Aegis's upbeat mood, and she instead got close to her to whisper, "I think we should release The Slayer."

Aegis's eyes went wide, and she briefly dropped the clipboard, but was barely able to catch it in time. "What?!" she whispered back. "Are you crazy?!"

"I came across some new information," Twilight explained, her voice slowly rising above a whisper without her noticing. "He's an enemy of Tartarus."

Aegis gave her a confused look. "How could you be so sure of that?"

Twilight faltered. "W- Well, uh-"

"Look, it doesn't matter right now," Aegis cut her off. "Either way, we need to clear it with the other princesses, first. We can't release anything we have here without a unanimous decision from you three."

"Well, alright then. Let's go get Celestia and Luna, then we can-"

"Then we can what, Twilight?"

Both ponies jumped at the arrival of Celestia, Aegis whirling around and backing up slightly so both princesses were in view.

"Celestia!" Twilight blurted out. "When did you get here?"

"I overheard some guards talking about you running through the halls. I was curious as to what the problem was."

Even though she already told Aegis, Twilight was much more hesitant to bring up the subject with her former mentor. "Well, uh..."

Aegis, meanwhile, was much more direct. "She thinks we should free The Slayer."

Celestia didn't visibly react, which made Twilight feel even worse. "And why is this?"

"I, uh... found some new information?"

Celestia raised an eyebrow. "Really? We've been researching him for countless years with no substantial results, and you found enough of a breakthrough after just a day of knowing about him to make a decision such as this?"

Twilight's wings started to droop. "I..."

"Twilight, I understand you're intrigued by The Slayer, but you must calm down. Assuming whatever you found was enough for you to make a decision, then we shall discuss matters with Luna."

Twilight still remained gloomy, but she felt a small glimmer of hope when she realized that Celestia hadn't outright denied the possibility. "I understand, Celestia."

"Well, I gotta attend to other business for now," Aegis said, starting to walk away. "If you three do decide to... well, let him loose, let me know, alright? I can whip the guards into shape for defensive plans."

"Thank you, Aegis." Celestia started walking in the opposite direction, and Twilight hesitantly followed, stealing a single glance back at the door hiding The Slayer.

"So what exactly did you find out?" Celestia asked after a while.

Twilight did her best to think up an answer that wouldn't hint at her methods. "I, uh, did some digging, and, well, I think The Slayer is... well, he's against Tartarus. Er, the demons of Tartarus."

Celestia seemed genuinely interested. "Oh? And how did you find this out?"

"It was... after I spoke with Discord about it," Twilight said, fabricating a lie for herself. "Something he said stuck out to me, and after doing some searching, I was able to track down some writings from one of the members of the Church of Discord."

Celestia looked like she wanted to object, but reconsidered. "Hmm, then I suppose that one survivor made it out okay," she muttered to herself.

Twilight was very much thankful that Celestia didn't spot her eyes nervously shifting about. "Yeah, w-well, it was a short anonymous account, only discussed in a collection of 'disproven' legends, but the facts line up. According to them, The Slayer was only fighting the demons at first, and he only attacked the Church themselves after they pledged their loyalty to them and then attacked him." Twilight noticed how detailed she was getting, and tried to cover her tracks. "Uh, or so it seems."

"Is that so?" Celestia asked, her voice stuck halfway between suspicion and earnest curiosity. "And where did they write it from?"

"Uh, northeast Equestria?"

"Really?" Celestia asked. "Because we had searched all around the area that would become Manehattan, and we found nothing."

"Oh, not in Manehattan, it was from the Baltimare area."

"Ah, I see." Celestia nodded. "You'll have to show us that passage then, Twilight. To think we've overlooked it for all these years..."

Before Twilight could internally panic about how to keep her lie going, the overhead intercom system crackled to life, followed by a stallion speaking over it.

"Um, could Princess Celestia please report to the Delta-Four lab? We're getting strange magical readings, here."

Twilight tilted her head. "Delta-Four lab?"

"Supposedly, it's an ancient, long-range teleporter," Celestia explained as she started walking down a branching hall. "Go ahead and find Luna, I'll be with you both shortly."

Twilight nodded, then watched as Celestia disappeared around a corner. She stayed put for a while, though, doing her best to think up a way out of the web of lies she found herself crafting.

Suddenly, there were red lights and alarms going off all over the labs, every single pony around her dropping what they were doing in response.

Rising above the sounds of the sirens, the intercom came to life again, this time with Aegis's voice.

"Attention, all personnel, report to the nearest shelter room! We have confirmation of invading forces, this is not a drill, repeat, this is not a drill!"

All at once, everypony started panicking, running down one of the halls that evidently led to one of those shelters. The guards appeared to be much more cool-headed about things, taking the time to more efficiently funnel the scientists the right way.

The intercom turned on once more. "This is Alpha-Two lab, we already have heavy losses! They're dem-"

The intercom abruptly cut off, but Twilight heard enough. A few guards called out to her as she galloped away from where they were herding the scientists, but she ignored them. The whole time, the intercom kept going, with other labs reporting similar things, some of them simply panicking and rambling for dear life.

Twilight had to hurry.

The door to The Slayer was now unguarded, but still tightly shut. Rather than try to figure out how to operate the door mechanisms, Twilight opted to simply teleport inside.

The room was bathed in red thanks to the emergency lights, making The Slayer's form all the more threatening. As she approached it, Twilight realized that she didn't really know how to get him out. They needed the Elements to free Discord, and she didn't have those anymore.

Then again, Discord was also able to break free on his own after a thousand years or so, and since The Slayer was imprisoned for just as long, the same could be done for him?

Aegis's voice cut into the intercom again. "We have confirmation that the invasion is demonic in nature. All guards, maintain posts near shelter rooms and kill on sight."

That announcement spurred Twilight on, and she reached out and touched The Slayer.

Once again, she found herself in the void, but it was more unsettling this time around. The voices were much louder, being incomprehensible screams. On the whole, even though nothing looked different, Twilight was heavily unsettled.

Galloping forward, she eventually came to the standing form of The Slayer. He was looking away, but as soon as Twilight got close enough, he turned around. The visions were starting again, but Twilight was able to look past them, albeit with much difficulty.

Once again, Twilight found herself unable to act under his vicious gaze, and the memories of what he did to those demons kept eating at her mind, pairing with the visions to almost petrify her to the spot.

Still, it was her only idea for freeing him...

Taking a few deep breaths and summoning every drop of her courage, Twilight forced herself to walk closer to The Slayer, the wails around them growing in frequency. She folded her ears down in an attempt to block some of it out, but it didn't help.

The Slayer walked forward to close the distance, and then reached for her. Twilight could barely see it, thanks to the visions, but she still managed to force herself to raise a hoof to meet his hand.

For a moment, nothing happened.

Then The Slayer forcefully grabbed her hoof, his grip burning to the touch.

Twilight screamed out of surprise and pain, doing her best to pull away, but his grip was unbreakable. The longer he held on, the hotter it got, and it even felt like the screams around her got louder.

Twilight could feel her own voice joining them as the burning sensation continued, no matter how much she struggled to pull back. However, it didn't feel like The Slayer was pulling her close, per se...

In fact, it was almost as if he was pulling himself to her.

Twilight made one last desperate jerk back, and for an instant, her entire vision was filled with the symbol on his helmet.

There was a crack, and everything went white.

Jolting awake, Twilight got back to her hooves and looked around. She was still in The Slayer's chamber, still bathed in that unsettling red light as occasional intercom announcements told her that, while the shelter areas were holding, the labs had already taken heavy losses, and the demons refused to stop.

Suddenly, there was a massive crack, and Twilight faced The Slayer. Slowly, his stone surface was cracking apart.

Despite the situation, Twilight couldn't help but feel slightly proud. Whatever she did, it seemed to have worked!

That pride was quickly overwritten by horror, however. She still had no idea how he'd react to finally being free.

Suddenly, The Slayer's outstretched arm broke free, sending bits of rock all over the room. Soon after, the rest of him followed suit, and he ended up falling forwards onto the ground, barely catching himself with his arms. Slowly, he stood to his full height, popping and cracking his joints as he did so.

His gaze locked onto Twilight, and she felt as if she had been frozen in place. No matter how much she willed her body to move, to say something, to do anything at all, it refused to cooperate.

As the intercom announcements continued, The Slayer took a few steps forward. Apparently, he had put away his weapon at some point, but after seeing him in action, that made Twilight even more afraid.

Once he was close enough that Twilight had to look up to meet what should be his face, she closed her eyes. This was it, she was about to die. All because she had to get involved in all of this.

She felt a grip on her back, and in a single moment her life flashed before her eyes.

There was a push, and then the grip was gone.

Shaking like a leaf, Twilight slowly opened her eyes. The Slayer was walking next to her, where she had previously been standing. It was as if she was simply in the way...

This revelation seemed to inspire her body to obey her commands again, and she turned to face towards him fully. "Is... it true, then?"

The Slayer stopped walking, and turned slightly. It was a minor movement, but it still made Twilight's blood run cold.

When he didn't say anything, Twilight continued. "You... you're their enemy, aren't you?"

He simply looked at her for a bit, until he gave the first actual form of communication she had witnessed from him.

He gave a small nod, then started walking to the door again.

Twilight was relieved that he seemed to harbor no ill will (to her, at least), so she nervously got closer to him. "Uh, give me a second, I can teleport back outside and open it from-"

The Slayer ignored her, opting instead to grab the spot where the two sliding halves of the door met. After a couple seconds of effort, the doors were torn apart, the metal screeching loud enough to make Twilight wince violently.

Thankfully, he stopped as soon as it was open enough to walk through, and she hesitantly followed. "I guess that works, too... But now we should-"

Twilight cut herself off as she saw the state that the rest of the labs were in. There was a thin layer of smoke starting to gather at the ceiling, but more alarming was the scattered blood splatters, occasionally paired with what was undoubtedly pony corpses. At least, the ones that didn't have just a stray limb. At the same time, she could overhear the sounds of screaming and fighting echoing down the halls.

Watching the carnage in the past was one thing, but being this close to such brutality, and done to ponies that she had most likely seen just yesterday, was enough to make her sick.

As she sat, dry heaving into a corner, she noticed that The Slayer was looking back at her. Not only that, but his body language seemed to imply... pity?

Once she managed to recover, Twilight started to shakily walk ahead of The Slayer. "The... the others should be in... a shelter nearby. You'll help us, right?"

As was becoming the norm, he gave no verbal answer, nor did he make any sort of noise. All he did was follow her, although he was scanning every hallway they passed, as well as a few vents that were in the ceiling.

By now, Twilight had adjusted to the violence enough to not shut down at the sight of it, so she tried to figure out the best way to find where exactly the nearest shelter was. At some point, they also came across demon corpses, alongside the ponies, although they were far fewer in number. Interestingly, The Slayer paused slightly upon seeing them, before continuing on.

She also noticed that he had pulled his weapon out again, although it was still pointed at the floor. It was almost identical to the way he walked out of that forest when Twilight first saw him.

In the meantime, she was trying to figure out the best way to find out how to get to the nearest shelter. As unsavory as it was, following the bodies was probably a safe bet, as was following the sounds of combat. They had gotten slightly louder since they started moving, but it was still impossible to pinpoint which halls they came from.

Suddenly, there was a crash behind them, and both Twilight and The Slayer whirled around to see a demon falling out of a ceiling vent, gracefully landing on its feet before assuming a combat stance.

However, once its eyes fell on The Slayer, Twilight noticed a minor change in its stance. As the demon let out a bone-chilling shriek, she noticed that it was starting to put more balance on its back leg, while subtly bringing its arms closer to its center.

It was... afraid?

She didn't get the chance to fully observe its behavior, as there was a blur of motion beside her, and the next thing she knew, The Slayer was right in the demon's face, before he grabbed hold of its head and swiftly brought it down onto his knee, completely obliterating it and leaving its headless body to crumple to the floor, creating a puddle of blood.

As she watched the spectacle, The Slayer simply turned around, and kept walking. His weapon was still present in his hands, so why didn't he use it?

After a moment of Twilight staring agape at the scene, trying to process everything, The Slayer nudged her, causing her to almost jump into the air, yelling.

"Aah! Oh, uh, sorry, I just..." She shook her head. "Moving on."

She started moving faster this time, with The Slayer falling into step, weapon now constantly aimed as he scanned the area around them.

By now, the intercom announcements had stopped entirely, and Twilight tried not to think about the implications. She could still hear fighting happening somewhere, so they weren't too late, right?

"This place really needs some signs," she muttered to herself, taking the two of them through different hallways to try and find the right path. Both the amount of corpses and the volume of the fight were growing, however, so it seemed like they were on the right track.

At some point, they also began to hear snarling and hissing, no doubt coming from the demons. The Slayer drummed his hands along the underside of his weapon, as if he was itching to find them so he could use it.

Above them, the intercom crackled to life again. "To all surviving guards, we have confirmation that the Delta-Four lab is the main source of the invasion. Make sure shield spells are in place around the shelters, and then move to neutralize the threat."

Twilight let out a small sigh of relief. "At least Aegis is safe..." And then she gasped. "Wait, Princess Celestia was going to that lab!"

The Slayer gave her a brief look, and then continued watching their perimeter.

Twilight started to speed up, going into a full trot, but he was able to keep pace with her perfectly. She just hoped that they'd be in time to help...

The demon sounds grew louder and louder, until they turned a corner to see a glowing blue shield covering a particular door. As expected, demons were clawing and beating at the shield, but she also noticed that there were a few bloody, shambling ponies beating at it, too. Twilight remembered the possessions she saw in the past, and shuddered. She imagined the process was likely much more horrific when the target was unwilling.

The Slayer didn't wait for the demons to notice them, and instead pulled out his rocket launcher. Before Twilight knew it, he had already fired one off, and she could only hope that the shield would be able to withstand it.

Once the rocket hit home, the horde was blown apart, body parts scattering the floor, with a few even hitting the ceiling. The shield flickered heavily upon detonation, but it managed to hold strong.

One of the possessed ponies managed to avoid being killed by the blast, so The Slayer bounded over to deliver a stomp to its head. Evidently, going that far forward exposed him to other demons that were around the corner, as he looked up just in time to sidestep an incoming fireball, which hit the shield instead.

Worryingly, it flickered a bit harder at that impact.

Twilight could only watch helplessly as another horde of demons descended upon The Slayer, who once again started to enact his deadly dance. However, Twilight was unable to observe most of the fight, as he would often run around the corner during the fight, leaving her to simply react to the battle based on the sounds of weapons exploding as they fired, skulls and rib-cages being shattered, and the myriad cries of the demonic forces.

All the while, stray attacks were colliding with the shield, causing it to flicker more and more every time.

Thinking quickly, Twilight closed the distance slightly, just enough to get in range. She then fired up her horn and cast another shield spell of her own, just behind the blue one. It was likely much weaker, but hopefully it would be enough to buy the ponies inside more time should their own shield break.

As she was doing this, she kept getting glimpses of the battle as The Slayer sometimes ran from one end of the hall to the other, demons either hopping backwards from him or chasing after him.

A few times, the fight transferred into the corridor that Twilight was still in, but she was able to take cover behind a support beam on the wall. It still didn't stop her from seeing the occasional flying limb, though.

After about a solid two minutes of fighting, she could no longer hear any demons, so she peeked out to see for herself.

And as she expected, The Slayer was the last one standing, looking at a shield spell that appeared to be on the brink of shattering on its own.

Twilight went ahead and dropped her own shield, just as the blue shield faded out entirely. She took the opportunity to gallop up to the shelter door, The Slayer walking up behind her.

Just as they were both in front of it, the blue shield started up again behind them, trapping them in a small bubble between the door and the rest of the hallway. The Slayer seemed slightly on edge about this new development, but he didn't do anything just yet.

Twilight knocked on the door. "Hello? It's me, Twilight Sparkle!"

At first, no one answered, but after a moment a voice spoke up from the other side. "How do we know this is the real Twilight Sparkle, and not some demon trick?"

She rolled her eyes. "Just open the door, please? The shield is up and everything."

There was some muffled debate behind the door, before it slowly slid open, just enough for a guard to start walking through. "Alright, come on, you... should..."

His statement died out as he caught sight of The Slayer, who simply gave him an unreadable look. Twilight didn't wait, and simply walked into the shelter. The Slayer followed, with the guard slowly returning inside and closing the door.

The shelter looked quite similar to military barracks, with ponies laying on all the beds, and a few in the floor. Medical personnel were scurrying about, tending to as many wounded as they could.

All eyes were on them upon their entry, and most of them froze on the spot when they saw The Slayer.

Further in the shelter, just out of view, Twilight heard Aegis talking to somepony else. "...situation is dire, but we need hooves on the ground right now."

The Slayer seemed to recognize the voice, and started walking through the crowd. They gave him a wide berth, eyes still wide, leaving Twilight to awkwardly follow.

"B- But ma'am, you've seen what those things can do! We don't stand a chance!"

"You're the best we got, and you stand a much better chance than anypony else here. Besides, Princess Celestia herself needs your help down there!"

They turned around a corner to find a makeshift command center, with a blueprint of the labs spread out on a table. Aegis was talking to a group of guards, who nervously looked between each other as she spoke. As soon as The Slayer was in view, however, they froze in place.

Aegis was facing away from them, so she continued. "We've already lost enough lives today, but I'll be bucked if I'm going to just sit here and hope they quit sometime soon. Now, I'll say it again: You will all go to the Delta Four labs to assist in combat operations, understood?"

The guards gave no answer, still frozen solid by the armored warrior that was walking up behind her.

Twilight took this time to speak up. "Aegis?"

Instantly, her stone cold demeanor was replaced with a far more friendly one. "Oh, thank goodness, Twilight, you made it... out..."

The Slayer was now in arm's reach of Aegis, and she just stared at him, her smile slowly melting into a horrified expression.

"T- Twilight...?"

"Uh, surprise?" she said sheepishly. "I, well, managed to get him out?"

Aegis just stared at him, wide-eyed. When he started to walk forward, she quickly shuffled out of the way. The guards also noticeably took a couple steps back.

While The Slayer seemed engrossed in the lab blueprint, Aegis turned to Twilight. "Are you insane?!" she whispered. "Do you know how dangerous he actually is?!"

"I'm fully aware, thank you," Twilight whispered back. "And he kept the demons from breaking through the shield."

Aegis glanced at his back, and the guards still keeping their distance. Suddenly, The Slayer looked directly at them, and they backed up even further, to the point where they collided with the wall and simply started cowering. He paid this no mind, and continued studying the blueprint.

"Think about the collateral damage, Twilight!" Aegis argued. "Even if he's not hostile to ponies, who's to say he won't end up killing everypony down here anyway?! We should-"

She was cut off when The Slayer suddenly reached back and grabbed her, and she screamed like a filly as she was quickly pulled to the side of the table. A few guards tried to step forward in response, but another look from The Slayer kept them in place.

Once it was clear that she wasn't being brutally murdered, Aegis stopped screaming and looked at him. His only response was to point at the blueprint, specifically at a room that was circled.

It took a bit for her to figure out what he meant. "U- Uh, that's where the d- demons are coming in, Mr. Slayer."

He seemed satisfied with the answer, but then he picked up the blueprint and held it right in front of her face, before pointing at the ground.

Aegis picked up the meaning, and pointed at one of the rooms that was marked with a dot. "W- We're here right now."

That was all he needed to know, evidently, as he simply nodded, tossed the blueprint back on the table, and then started walking back out of the room.

Twilight had simply watched events unfold with bated breath, but was shaken into action when The Slayer brushed past her. "Hey, wait!"

He did not wait, and he made his way back to the entrance of the shelter, where a guard was busy keeping up the shield spell. The Slayer tapped him on the shoulder, making the guard jump almost a full foot away while dropping the spell. When The Slayer pointed at the door, he seemed to understand, and pulled a nearby lever to open it.

By now, Twilight had caught up to him. "Hold on, wait for-"

Continuing to ignore her, The Slayer ran back into the rest of the labs, the guard quickly closing the door behind him and firing up the shield spell again.

"...me..."

Aegis trotted up beside her, as they started to hear the faint sounds of combat and explosions outside. "Twilight Sparkle, you have released probably the most dangerous creature to ever step foot in Equestria, and now it's loose in our labs, in the midst of a demonic invasion."

Twilight winced at her tone. "We were being invaded, and..." She sighed. "I knew that, if nothing else, he could handle the demons."

Aegis paused before continuing. "I'll ask how the hay you knew that later. For now, we should see about securing an evacuation plan for the ponies here."

They could just barely hear the sounds of a muffled chainsaw from outside, and everyone present winced.

"Is that a chainsaw?!" a nearby guard asked, before muttering to himself. "Sweet Celestia, we're gonna die..."

Despite the situation, Aegis let out a dark chuckle. "Honestly, I think she's in a lot more danger than we are, now."

Walking over to the nearby intercom system, she pushed the button and spoke into the microphone.

"All personnel, be advised, The Slayer is now free within the facility."