"So sister, what's so important that you had to pull me from my dream duties tonight?" asked Luna curiously to her elder sister, "Not that I mind going on another adventure with you - seeing as how we barely get out together anymore" she added hastily.
Through the night time sky, the two royal sisters zipped across the treelines of the Whitetail Woods, flying so fast that it would have made a particular element of harmony green with envy. Due to the seriousness of their mission, Celestia saw fit to have Luna suspend Night Court for the evening and depart with her immediately at full speed, but as usual not without considerable protest from their subjects.
Such was life when you had prestige and status akin to that of 'living goddesses'. Every movement was heavily scrutinized and gossiped, so much so that by the time the news reached the press, stories were already completely out of hoof with the original account. It also made independent actions heavily tied down to the machinations of bureaucracy, with ponies constantly demanding to know where they went and why they were going.
Thank the stars for Blueblood stepping in, thought Celestia. She really should do something for her estranged nephew when she gets back to Canterlot. Despite his horrid personality and Luna's immense dislike for him, he was still a loyal stallion at heart that could always be counted upon, especially due to his talents in the fields of bureaucracy and his connections to the upper class. It was also a good thing that unlike the rest of them, he didn't bother to ask where they were going tonight.
This is a matter that only me and my sister should know, thought Celestia bitterly as she redirected her attention back to her younger sister flying beside her. "Do you still remember the whole Tirek debacle?"
"How could I not?!" frowned Luna back, "I still can't believe you convinced me to let that traitor Discord off with nothing but a slap on the wrist. If we were back in the olden times, he would have been in the stocks for at least a week"
"Yes, but we are no longer in the olden times Luna," said Celestia patiently.
"Can't a mare dream?" Luna smiled mischievously as she rubbed her hooves together, "Just thinking of all those rotten tomatoes I could have pelt at that accursed draconequus gets my heart racing every time"
"Yes, yes. The Discord business aside. Ever since the whole Tirek situation, I can't help but feel constantly worried about something" sighed Celestia, the fatigue evident in her eyes. Luna wondered to herself how much sleep her older sister's been getting since the whole incident.
"What is there to be worried about? Good friend Twilight Sparkle has already defeated him and she has gotten an amazing castle out of it. Discord, as much as I dislike him, is back on our side, and the monster Tirek is once more rotting in his cell in Tartarus"
"Yes, but how Tirek got out of Tartarus in the first place is what I'm trying to figure out" insisted Celestia.
"Did we not come to an agreement that it was because Cerberus left his post at the gates?"
"But Cerberus isn't the only mechanism placed there to prevent escapes. There are plenty of other magical mechanisms in place" Celestia gave a steely-eyed look, as the peaks of two mountains came over the edge of the horizon, "I intend to find out how he got out, despite all of them. And if he's not the only one to be freed"
The two sisters continued to fly in silence as they descended to the entrance to Tartarus tucked away carefully inbetween the crevices of the mountains. The entrance was a massive golden door; towering several feet into the side of the mountain and surrounded by pits of flaming lava, a distinctive lack of vegetation, and a sharp smell of sulfur that all kept all inquisitive animals and ponies away from the door. Not that they would have been able to forcibly unlock it by hooves.
Celestia and Luna stood side-by-side, their horns flaring with magic as they concentrated on the ancient spell taught to them by Starswirl the Bearded, the only spell able to unlock the doors to the prison. Two beams of light erupted from their horns, golden for Celestia and aquamarine for Luna, combined to hit the door, slowly but surely opening the heavy doors with a loud groan.
A jubilant Cerberus met them at the entrance, his three heads panting in excitement as he pounced upon the two sisters and gave them both affectionate, and slobbery licks to the face.
"Down boy!" laughed Luna as she returned an equally affectionate hug while Celestia detached herself from the dog, "Who's a good boy?! Oh yes, you are, oh yes, you are~~!"
Celestia smiled as the three-headed dog laid on his back to be scratched, her younger sister complying as she dug her hooves into his furry underside. With every scratch, Cerberus's whines got louder and louder, with Luna digging further and further in with joy.
"Pathetic"
A rustic voice broke their moment of happiness, Luna especially who then turned her attention to the other creature besides Cerberus in Tartarus.
"Tirek" sneered Luna, "How horrible to see your ugly mug again"
"That's Lord Tirek to you! You impudent wretch" snarled the centaur, the knuckles on his clenched fist white as he gripped again the bars of his cage, "And the feeling is equally mutual"
"Meh" Luna flew over until she was level with Tirek's face, "The only ones I call Lord are those I deem worthy of respect. Also if the stallion is big enough to please me. You..." her eyes skimmed down for a moment, "Seem to be lacking in both departments"
She cackled, springing back as Tirek's claw shot out of the cage in an attempt to graze her face with his nails.
"You think you've won?!" snarled Tirek through his teeth, "Just you wait...once I get out of here and regain my strength, your magic be the first one that I drain! And I'll make sure to take it nice and slowly. Just like how you drove me mad down here!"
"Hmm...taking it nice and slowly is a very tempting offer" Luna placed a hoof to his lips and gently pushed him back, forcing him to the cold floor of his cage in an undignified fall. She glared back at him with just as much venom as he did to her, "But you are not getting out of here to hurt anypony a more. I will personally make sure that scum like you will never see the surface ever again!"
"Oh yeah? And how do you plan to do that? If your plan is just that dumb mutt by the door then - oooOOOooo I feel so threatened?"
"Leave it up to me and Celestia. Once we are done here I'm sure we will have a contingency plan - right sister?" Luna's was confused as she didn't hear a response from her sister. Turning around, she only saw the backside of the solar monarch staring at the empty cage next to Tirek's, "Sister?"
Wordlessly, Celestia swung around and slammed her hooves onto the bars of Tirek's cage. The golden hoof shoes collided with the magically-enchanted metal, rattling the entire structure.
"Celestia!" screamed Luna, shocked at the force of the strike.
"How did you escape?" asked Celestia coldly. There were clear venom and malice dripping from her voice, such a large degree of it in fact that it also made Luna instinctively take a few steps back. For as much as she despised Tirek, she had to admit she was quite impressed by how defiant he was as he stared back at the furious princess in front of him.
"Celestia," said Tirek with equal disdain, "Might I say that your cake-eating habits haven't done wonders for your flanks. You might want to consider that next time"
"ENOUGH!!" She slammed her hooves against the cages once again, this time causing Tirek to stumble quite a bit from the force, "I will ask this again. How did you escape?! Or rather how did all of you escaped?!" She motioned to the other empty cages, something Luna had neglected to notice up until now, "Answer quickly, or else!"
"Oh yeah? And what if I don't answer?" He gulped as her horn crackled with magical electricity. It was then that Luna decided to step in.
"Sister! What are you doing?!"
"Luna, I-!" Celestia hesitated as she saw her sister's worried and frightened eyes. Taking deep breaths to calm herself, Celestia composed herself as best as she could and turned to her younger sister, "Please...let me handle this. I'll explain all of this afterward. For now...just...check the evidence room for me. Especially under the locker 2B"
"Um...sure" replied Luna as she uneasily took flight and flew to one of the caves of Tartarus. Its been a while since Celestia asserted her influence as the eldest sister. In fact, ever since Luna returned from the moon, there hasn't been a single time which Celestia ordered her to do anything she didn't want to. She had constantly stressed that the two of them were equal. That one would never be higher than another.
The oldest memory that Luna had of Celestia's domineering personality...was when they were younger. To see her once again express this dominant side of her...it worried Luna.
"So...taking the initiative once more, huh?" Tirek clicked his lips mockingly as he watched Luna fly off into the distance, "When can I expect a Nightmare version of you- AAAAAAHHHHHH!!"
Tirek fell to the cold floor as torrents of electricity shot out from Celestia's horns and consumed his broken body. The force and heat of the electricity forcibly kept him down as he felt the pain shot through his body and fry his insides. Had he been stronger and in his ultimate form, he might have been able to laughably shake it off. But he wasn't. He was relegated to this miserable state when they drained him of his magic, so even Celestia's modest attempt at a high-level lightning spell was able to douse him with immense pain.
He didn't die though. For as Celestia stopped her magical flow and Tirek laid on the ground panting in pain, the magic imbued within the walls of Tartarus worked their way up and healed his wounds.
"I...Will answer me now?!" Celestia looked just as exhausted as he was as she glared at his pitifully, charred body. Her horns lit up once more with a golden glow, "Or will another bolt loosen your tongue?"
"Alright- cough- cough- you've made your point clear as day" Tirek spat out clouds of smoke while Celestia sat down in front of his cage, "You ask how I got out? How every other prisoner got out? Simple, hehe. He let us out"
"Who?"
"I think you already know" replied Tirek smugly as he indicated to the empty cage beside him. Celestia's heart dropped with every second she spent staring at the cage as the worst of her fears made itself true to her
"No..." she whispered quietly.
"Ah, but it's true"
"That can't be! He doesn't have any magic?!" Celestia was sounding hysterical by this point, "How could he have broken you, no, all of you out?!"
"That, I do not know, Celestia" Tirek sounded bored, but Celestia could see the clear joy he was getting out of her distress, "See I was staring at my wall, counting the number of years I've spent down here. Like I always do. That was until there was a kick at my lock. There he was on the other side, bite marks all over his arm, with a grin on his face. His cage was already unlocked"
"He asked me if I would like to leave. I told what was the catch, he said there was one" Tirek pretty much leered at Celestia, allowing her to stare into his sickly yellow pupils and black sclera. "The only thing I had to do was destroy Equestria as much as I could. I agreed to it. And then he let me out"
"How did he break the locks? These are magically imbued locks with resetting and immunity charms. Nothing should be able to break them, except me and my sister" She took a closer examination of the locks, both the other cages and Tirek's. Nothing on their surface indicated any forms of damage made to the exterior. Could it have been from the inside?
No. That was not possible either. Cause in addition to resetting and immunity charms, they also had tracking spells. Any abnormality and Celestia and Luna would have known straight away. That could only mean that these locks were manually unlocked. But then why did they reset back to their locked stage afterward?
"Did you get a glimpse of how he unlocked the cages?" asked Celestia, this time without any of that air of authority before. She sounded just like the usual Celestia, albeit a much more focused one.
"Actually I did" replied Tirek uneasily as he took notice of her sudden shift in tone, "He fiddled with locks using two white things, not that I could see them"
"Do you know what they are?"
"No. But..." Tirek scratched his chin for a moment as he pondered back to that time, "He was missing a digit on his hand - now that I think about it. The last one to the right on his right hand. Not sure if that's helpful or not"
"Hmm..." Celestia chewed her lips as she considered the possibility of what Tirek was insinuating. Could he have used his own fingers as lockpicks? No, that idea was absurd, even within its own right!
"SISTER!!" Luna's panicked voice broke her out of her concentration. The princess of the night emerged from the tunnel that led to the evidence locker, perspiration dripping from her forehead as she leaned against the walls to regain her breath.
"Luna!" Celestia flew over and wrapped a wing around her sister, "Are you okay? Are you hurt in any way?"
"I am fine" Luna pushed herself up until she was level with Celestia, "Locker 2B - it has been picked clean!"
"Clean? Are you sure?" panicked Celestia. This situation was quickly becoming worse by the minute.
"Completely clean. There is nothing left there"
The doors to Tartarus slammed closed with a loud thunderous boom, drowning out the angry protest of the centaur locked inside as the two royal sisters proceeded down the rocky steps of the entrance.
"HOW DARE YOU!! I AM LORD TIREK - I'll BE BACK! JUST YOU-"
"So now are you going to explain to me what you so worked up, sister?" asked Luna as she stretched her wings for the inevitably long flight home.
"I...I think it's time" sighed Celestia, "Do you remember the first enemy we've ever fought as newly-crowned princesses?"
"How could I not?" Luna jumped on a rock and posed dramatically, "Those were definitely the days. The tension! The fact that every battle could decide the fate of a nation! The sheer power of our battles against evil moved the very planet itself! Was it not Tirek that was our first battle?"
"No, it wasn't. Do you not remember?" asked Celestia with genuine concern.
"Must be the lack of oxygen on the moon" Luna tapped her head lightly and pouted, "A thousand years go by and my memory is still fuzzy. If it is not Tirek, then whom do you speak of, sister?"
"Do you remember the 'Monster of the Everfree'?"
"Afraid you are going to have to be more specific with that one, Celestia. If my horrible memory recalls, we have conquered many creatures worthy of the title of 'Monster of the Everfree'"
"Does the..." Celestia hesitated for a moment, the horrors of what she remembered holding her back as she considering telling this to her sister. But she did make a promise to tell her sister, "...mentions of p-pony heads on spears remind you of anything? Or maybe the pegasus feathers on his helmet? What about the manticore furs he wore over his armor?"
Luna because deathly quiet as her jaws fell open, the shock and repulse visible on her face as a tinge of green appeared her cheeks.
"N-no way! That 'Monster of the Everfree'?!" exclaimed the shocked mare.
"The same one" Celestia turned to stare at the moon in the night sky, a habit she picked up over the years whenever she felt the strains of her past find their way into her present. Often it was her sister, her image on the moon a constant reminder of her wars.
Now though, it seems another one of her past was coming back to haunt her, haunt both of them in fact. Celestia could only dread to think about what the monster could be doing, at this very moment.
"Should we tell Twilight Sparkle about this?" asked Luna cautiously as the two of them sprung up and took flight, "This is an extremely serious case!"
"No" sighed Celestia, "Let her and her friends bask in their victory over Tirek...for now"
"But we are going to do something about it, right?! Such a monster cannot be left unchecked! Especially if he had retrieved his artifacts!"
"Believe me when I say I would love nothing more than to do that. But along with Tirek, he's released every creature we've ever locked away in Tartarus. The Chimeras, Bugbears, Hydras and the such, those are our main priorities for now. I believe S.M.I.L.E might require a significant budget boost in the next edict"
"But all of that aside" Celestia stared fearfully at the lights of civilization in the distance, "I just hope we won't be too late when we do confront that monster once more"
