As the Slayer stepped out from the portal into the Fortress of Doom, Dr. Hayden congratulated him. “Congratulations, Slayer. Place the necklaces beside the crucible power source.”

The Slayer did as he was told, placing the necklaces beside the Crucible in the floating cylinder of energy used to power the ship. As the lights flickered and more things hummed, Dr. Hayden said, “Slayer, head over to the fabricator. There are new weapons to manufacture.”

The Slayer stepped over to a computer console next to a machine. In front of him were 8 weapons to select. He already had the combat shotgun, so he opted to create his Super Shotgun, Auto Rifle, and Ballista. After a moment of machine sounds, his new weapons were fabricated. Without hesitation, he threw away the guns he grabbed at the base. He attached the Destroyer Blade to his ballista, placing the attachment into its core, and slapped the Precision Bolt attachment to his rifle. With these new weapon upgrades, he could let out super-powerful, wide laser blasts and shoot large, dart-sized hunks of steel with ridiculous speed.

“Slayer, it will be several hours before I am able to create another portal due to generally damaged power systems. I recommend you take this time to test your weaponry at the range and rest.” The Slayer nodded, and subsequently made his way into the demon prison, which now lay empty. He took out his weapons, selected a few barrels as targets, and began to sprint around the arena, shooting his targets with inhuman precision.

After testing out his newly acquired tools of raw destruction, He returned to his office to generally tinker with them and make sure they were tuned to his liking. After about 6 or so hours of waiting, with the slayer popping open some books on his shelf, Dr. Hayden called him up.
The Slayer grabbed his new pony-destroying toys before sticking them behind his back, simply thinking of the pocket dimension he typically used to store his massive arsenal. He then made his way up, entering the bridge portion of the Fortress of Doom. Dr Hayden gave him some target information as he stepped up to the teleporter.

“Slayer, I am linking the portal to London, Britain. The city is one of the few places holding back the Pony Hordes. The ponies have a powerful offensive there, and you will need to break their lines and obtain their power source. With it, we can power up even more weapons, and I may be able to even fabricate a BFG clone.”

The Slayer nodded, taking in this convenient exposition, before pushing down on the portal start-up button on one of the nearby desks. He then looked into the swirling black-and-blue vortex before him, stepping into it, ready to bring divine retribution upon the accursed ponies.

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The sun slowly fell over the city of London, a once jolly-good pub-riddled haven for the average British man, now turned ethereal magical warzone where human rebels held fast against the xenophobic multicolored mini-horses. As Applejack and Rainbow Dash trotted through their camp, they heard gunfire and spells in the distance.

“Hey, Rainbow, Ah’ve been thinkin’ about this here… War, and ah’ feel like Celestia ain’t tellin’ us somethin’. When she sent us on this front, ah’ could tell that she wasn’t speakin’ the full truth,” Applejack said, as she trotted to her quarters. “Don’t get me wrong, ah know the princesses always know what to do an’ all that, but ah’ can’t help but feel confused about what she could be hidin’!”

Rainbow Dash sighed. “C’mon, Applejack. We’ve been over this. The Princess would never lie to us! Even if she did, It’d still be for our own good! Honestly, I think you're just a little… well… paranoid.”

As the two stepped past the elite guardsponies outside of their tent, they split up to their separate “rooms”, which were more of just two halves of the tent, separated by a roll of cloth. As applejack lay in bed, she began to worry. First, her recent doubts about the princess, her worries about the morality of this mass conversion, and the troubling reports of the “Ponyslayer”, which spoke of a heavily-armored human with advanced weaponry who single-handedly destroyed the entire Mexico offensive.

As she mulled over these thoughts, she absentmindedly said, “‘G’night, Rainbow dash,” as she drifted off into a restless sort of sleep.

[]========== [][][][][][][][]==========[]

The Slayer stepped out of the portal to find himself atop a bridge with tall towers and an observation deck, which seems to have been abandoned. As he overlooked the city of London, the once vibrant city lay dark and dead. As he stared out into the vast city, Dr. Samuel Hayden called in.

“Slayer, welcome to London. You are currently located on top of Tower Bridge. This area of London appears to have been overtaken by the ponies. The human resistance is scattered around, and the remaining survivors seem to be using Guerilla tactics, where they strike from the sewers. The British military also sends the occasional patrol to fight the ponies off, but they have already secured over half of the city. It has been locked in a struggle for weeks now. The necklaces are located inside Buckingham Palace, but their wielders appear to be at the pony front lines. Head towards the marker on your HUD for an optimal entrance, Slayer.”

The Slayer nodded, turning towards the marker, and jumping from the tower with no hesitation. He landed with a loud thud, and he began to jog towards the HUD marker. As he jogged down the street, he passed several buildings, wondering to himself where the ponified humans went. After about a minute of jogging, Samuel Hayden spoke.

“Slayer, take cover. There is a large force of ponies passing by, and they may scatter and call an alarm if they see you.” The Slayer reluctantly nodded, turning towards one of the nearby narrow alleyways and ducking behind a trash can. As he took cover, a large platoon of approximately 30-ish ponies marched by, in perfect columns. What troubled the Slayer was that many of the ponies were wearing the power armor he’d seen before. Sure, they could not harm him, as he was far too strong, but they would be more resistant and annoying. He let them pass by without trouble, before continuing on his way as the night went on.

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After the Slayer snuck his way to the buildings near the palace, he scanned for guards and ponies. He saw the main doors guarded by four advanced-looking power armor ponies. He saw several lookouts through the windows as the weather had started to change and dark, thick clouds began to gather in the sky.

“Slayer,” Interrupted Dr. Hayden, “I will scan the building and find you the way in.” The Slayer’s helmet began to whir quietly, and slowly, the building’s layout was displayed to the Slayer, with a path lit up in green.

“To enter without alarming the ponies, you need to enter through this tunnel from the nearby buildings, Slayer. The door on your left should do it.” Dr. Hayden started coldly, but the Slayer was sick of sneaking around. He simply turned to look towards the main doors for a moment, and without a word, took out his Super Shotgun. It was time to test his new weaponry.

[]========== [][][][][][][][]==========[]

Captain Thunderhorn stood tall at attention, scanning the outside of the palace for any possible threats. Inside this former human royal dwelling, there were some of the most important artifacts for the war, the elements of Honesty and Loyalty. He breathed a sigh of disappointment as he saw the rain clouds come into position overhead. “Command should have some pegasi manage weather over these damnable human cities...” He thought to himself, as his boredom from his long guard shift grew. As his attention began to wander to his thoughts, he heard one of his subordinates shout.

“Oi, Cap, what does that look like to yo- OH BUCK, MOVE!” Shouted one of his younger troopers. The Captain turned towards the sound and saw a flaming orange ball hit the ground beside him. All he felt was heat before his entire world turned into a brilliant flare of white.

[]========== [][][][][][][][]==========[]

The Slayer watched as the pony closest to the grenade had half of him vaporized in the blast as the other ponies were flung all in different ways. Only one was left standing, trembling and shaking, turning his head towards the point of origin of the explosive. The Slayer didn't care about their puny armor, he was here to avenge humanity. He then rapidly charged the ponies before coming close enough. He then stopped, shooting out the flaming meathook from under his Super Shotgun. With a loud clunk, it connected with the last standing pony, and the Slayer jumped forward, flying towards the pony at high speeds.

As the pony lost his balance, the Slayer reached him and point-blank fired both shells into his body. This punched a hole directly through the magic casing around the armor, turning the pony’s insides into a fine red mush reminiscent of ground beef. He then turned towards the two survivors who were standing up and rapidly swapped to his Auto Rifle. He quickly aimed through the scope, blowing a quarter-sized hole into the closest one before he could react, spattering his brains out onto the floor. The other pony could only scream as the Slayer activated his arm-mounted blade, and ran directly at him, slamming it into his skull over and over again.

The impact from multiple hits alone shattered the skull and turned his brains into mush, until the Slayer penetrated, utterly destroying his skull. He then heard screams of terror from inside the palace, noting that the sentries posted at the windows had both seen and heard him.

With a sigh, Dr. Hayden began speaking. “You have alerted the guards, Slayer. Now you must destroy them all. Luckily, you excel when it comes to that, so I expect it done quickly, Slayer.”

The Slayer nodded, reloading his Super Shotgun before going over to the large doors, which were now locked. He took out his chainsaw, revving it up, before sawing a hole large enough for his body. He looked inside to see the main stairwell area filled with armored ponies, who all had their turrets pointed towards him. He then ducked behind cover before launching two grenades inside in rapid succession. As the loud bangs and flaming explosions took out a solid dozen ponies each, he stepped inside with his combat shotgun set to “Sticky Bomb Launcher” mode. He rapidly shot five smaller bombs onto various still standing targets, sending them flying into the nearby walls, dying on impact.

He then swapped to his auto rifle, wading through the dazed and half-dead ponies, finishing them off one by one with well-aimed, close-ranged precision bolts. As he finished off the last pony, he heard the commotion from behind him. He looked at the door he just entered through, seeing the dozens of armored ponies that had passed him earlier enter, rushing in to stop him. He then began to run circles around the room, narrowly avoiding blasts from their back-mounted cannons while launching stickies and grenades at them. Suddenly, the door flew off of its hinges, and a massive pony, almost as tall as him, rushed him directly with insane speed.

“RAAAAAGH! PREPARE TO DIE, HUMAN SCUM!” Shouted the massive pony in full power armor as he charged. The Slayer turned to face him, wordlessly activating his arm blade and winding up a punch. As the massive hunk of metal of a pony rammed into him, he punched him in the skull with all his might, slamming a hole directly through the heavily-armored skull of his massive opponent. The deafening screech of metal was heard as the pony slammed into the ground, scratching and cracking the tiles of the floor. This, however, didn’t stop the momentum of the now-dead pony from sending the Slayer flying into a nearby wall, sending him tumbling down. Seeing this as their moment, the few remaining armor ponies quickly fired at him, but he barely managed to roll out of the way, crawling over to the dead mega-pony and using his metal-clad body as cover.

The Slayer then swapped to his ballista, rapidly charging up a Destroyer Blade shot before peeking out of cover and firing. With a loud blast, raw heat and energy flew at blinding speeds, rending flesh from armor and melting the pony magic on contact. As screams of agony filled the room, the Slayer looked over his handiwork with satisfaction, watching the now severed bottom halves of the armored ponies slowly fall apart, before turning and making his way up the stairs into the room where the Elements are held.

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Gambit Queen was panicking. She had recently been placed in command of the entire offensive, and now the bucking “Ponyslayer” from the Mexico incident had arrived at her base, presumably for the two elements she had in her care. She was a tactician, not some rough-and-tumble combat pony, and she was not at all expecting this massive threat. As the entire command room stared at the Scrying Crystals that showed the carnage, she gulped with fear, glancing at the elements that were held in a crystal casing in the center of the room.

“A-a-alright, e-everypony, we need to… uhh… qui- AAAAAAAAAAAGH-” She sadly never got to finish her sentence because the Slayer had already broken through the door, burning a hole clean through her chest with a single ballista blast. As she quickly blacked out from the raw agony she felt, she saw the guards rush the Slayer, knowing that it was futile. As she slowly died, a whisper escaped her lips.

“The p-p… Ponyslayer...”

While she drifted off into eternal sleep, the sounds of gunfire and crumpling armor filled the room as the blood of guard ponies and officers splattered everywhere.

[]========== [][][][][][][][]==========[]

The Slayer, once again, waded through many dead bodies towards the large clear crystal cases that housed the two Elements he was here for. Wordlessly, he slammed his fist through the case, grabbing the Elements and placing them on his belt.

Dr. Hayden then spoke. “Good job, Slayer. You will need to leave the building so I can find a suitable exit portal location. Follow your HUD for info.”

The Slayer looked at his HUD map and began to follow the path leading him up the stairs. He quickly made his way through the palace, before turning into a maintenance hallway that led up to the roof. He made his way through the doors and entered onto the roof, looking around. He saw Dr. Hayden’s marked position and turned towards it, walking calmly while looking out over the city of London. As he impatiently waited for Dr. Hayden’s portal, he overlooked the city of London as the sun began to rise. He saw smoke rising in the distance, signs that there were still firefights happening all over the city, but chose to not think of them. Rather, he had a moment of relaxed peace.

Right at that moment where he rested for but a second, a loud, ear-piercing boom was heard from behind him as he rapidly rolled out of the way of a bright, rainbow-colored streak of hair passed him at Mach speed. He turned to see a dozen flying Pegasi, each wearing an advanced armor set, flying in formation with a chariot attached to a few of them. As he watched the chariot land a few hundred meters away from him, he took out his ballista, preparing for combat once more.

The flying rainbow Pegasus landed beside it, taking a fighting stance, followed by the Pegasi behind her forming up as well. An earth pony then stepped out of the chariot, preparing to charge him. He almost chuckled at the pony's foolishness and pointed his ballista towards them.

“Alright, so-called “Ponyslayer”. Prepare to meet your demise!” Rainbow Dash shouted, tensing her legs up, preparing to spring into the sky. Applejack simply took out her lasso and began whirling it around. The Slayer rapidly flicked towards Rainbow Dash, shooting his ballista, but she quickly flew out of the way and began to circle him from above. The armored Pegasi then swooped down to attack, with several flying towards the Slayer in tandem. They activated wing-mounted crystal cannons, blasting rays of energy at the Slayer, but he rolled out of the way before crouching down and jumping up almost 5 meters with explosive power.

Before the Pegasi could react, he had grabbed them both by the neck, dragging them down and slamming their skulls into the gravelly roof of the Palace. A sickening crunch of bone could be heard as both slumped over, dead on the spot. He then turned to face the next two, who were more hesitant and flew higher. He shot at them with his combat shotgun, missing several shots. The Pegasi then flew back to rejoin their formation, and subsequently exploded, causing all the pegasi to fall to the ground.
The Slayer had only missed his shots because he was busy landing a single sticky bomb that made all the difference. As the remnants of the flying Pegasi fell to the ground, Applejack had enough, rushing toward the Slayer with unexpected speed. At the same time, Rainbow Dash flew up into the air, arcing downwards and beginning to reach supersonic speeds, streaking towards the skull of the Slayer. As Rainbow Dash reached him, the Slayer simply stepped out of the way, causing Rainbow Dash to crash into Applejack at ridiculous speeds. With a loud crash, followed by several sounds living skeletons should not make, both of them were knocked out by their impact.

The Slayer then turned off towards the HUD mark, stepping to the edge of the roof as a portal opened before him. He looked back, wondering how the remnants of humanity were dealing with ponies, before stepping into the portal. As the sun rose over London, the dome pony shield that protected the Palace and other landmarks fell, and the Slayer made off once again with what he needed.

Author's Note

Well, i fucked off for a while. kinda forgot i was doin this, but got my writer mojo back and went at it.

also saw another conversion bureau x doomslayer crossover story, it was solid.
once again, please constructively shit on my writing so i may improve, thanks.

i will have chapter 4 of the doomslayer vs small horsey chronicles done in a week plus a few days (probably), and i promise to not fuck off for a month