Inside the Red Bastion, the only light came from Twilight's burning mane, casting eerie purple shadows over the strange moving gears and rather distressingly organic shapes moving with a distinctly biological grace. It was like being in a living machine, Twilight felt, that was extremely loud and reeked of death. She tried calling out, but couldn't even hear herself over the grinding machines. The machines themselves, once she walked closer, seemed to be gears and arms made of some kind of silvery metal, and served no real purpose she could see: endlessly pumping and turning, sometimes without any apparent means of locomotion. Periodically a reeking gout of some dark fluid would wash over the metallic parts from some spout in the ceiling, presumably for lubrication purposes, but the machines seemed to drink it in, working faster when the liquid washed over them like some sort of strange creature feeding on whatever it was in the noxious liquid that sustained it.

Twilight turned and found that her guide, Scum, was clinging close to her and she couldn't bring herself to shake off the wretched creature. Scum trembled against Twilight, bits of his mane falling out periodically, his drowned-looking flesh quaking with quiet terror, and for a moment, Twilight felt bad about forcing him to guide her. Still, she had to save Applebloom, and Scum had been torturing ponies, albeit without any real malice. She was about to say something comforting to Scum when a hook attached to a mechanical limb shot out and pierced Scum's side, causing him to scream. Before Twilight could blink, the vicious limb pulled Scum into the darkness above, lifting him painfully out of her sight, screaming all the while.

More hooks shot out of the darkness, aiming for Twilight, who started running through the strange halls, dodging metal hooks and limbs, their cruel barbs glistening with the foul lubricant that sprayed from above like the last fell gasp of one of the ancient gods of plague. One barbed hook snagged her apple basket and pulled Twilight over, and would have dragged her off if she hadn't blasted it with her magic reflexively. A deep rumbling scream echoed from above, and suddenly Twilight found herself dodging twice as many hooks, blasting those that got too close: either melting them to impotence or fusing them to the floor where the attached arm flailed uselessly.

A light glowed ahead in the thrashing darkness, which resolved into an EXIT sign, which seemed very incongruous in that nightmarish place. Still, with nowhere else to go except back the way she came, Twilight made for the distant green sign, which proved to be attached to a wall, above a door with a simple push-latch. She burst through it ahead of a mass of grasping hooks and found herself in a stairwell that rose into darkness, while the hooked appendages thrashed through the open doorway in apparent frustration. Twilight snarled and slammed the door shut magically, fusing it with a blast of purple fire from her mane, the metal sealing the arms to the doorframe.

Inside the stairwell, the unicorn found herself with room to breathe. No hooks threatened here, no machinery ground its ponderous mystery upon her eardrums, and no reeking fluid rained from on high; the only thing the concrete interior of the stairwell smelled like was dust, and the only sounds were her own breathing, a distant bass thumping and the thrashing of the barbed hooks against the door she'd just entered, while the only light came from the flickering of her burning mane, which was now as large and magnificent as her mentor's, but filled with an eldritch collection of symbols and words, which she recognized as bits of magical formulae.

Twilight sighed softly, confused, and conjured a white light mote to look herself over, one of the simple spells from her time training under Celestia. She immediately wished she hadn't checked: Twilight's coat was matted with blood, which explained the horrible reek of the dark fluid and gave the machines a decidedly macabre feeling. She winced as it reminded her of Scum, who had been taken by the dark hooks, to some unknown fate, and that reminded her of Applebloom, who may be suffering worse than this while she fretted about blood in her coat and the fate of a torturer.

Twilight's lips set into a frown as she looked around the stairwell for some clue as to an exit, she still had one hollow to go through after this, and without her guide it could take her a while to get there. She found what seemed to be an escape diagram laminated on one wall: it depicted a pony running up the stairs, into a room at the top where the word 'EXIT' was printed neatly above a giant eye. With no time to interpret the strange diagram, Twilight looked up for how far she'd have to go, flaring her magic to show how many flights of stairs she'd have to climb. The stairs stretched into the darkness, beyond the range of even her puissant light spell.

“I don't have time to climb this!” Twilight said to herself, her voice echoing strangely in the concrete stairwell. Then she noticed, the stairwell was a spiral running along the inside of what was essentially a giant tube. The purple unicorn licked her lips nervously, she'd never tried flight before without wings, but she didn't have time to make the butterfly wings she'd crafted for Rarity so long ago. She closed her eyes and began to focus her magic, whispering to the shadows to help her, and listening to the advice of the ever-present darkness.

Twilight's mane of purple fire formed a circle around the dusk-colored unicorn, and oozed into designs of power and command that floated around her like adoring spirits. Twilight's mote of white light went out, then she bunched her legs under her like Rainbow Dash taking off and leapt up, completing the spell. Twilight flew up the center of the stairwell like a purple comet, passing hundreds of flights of stairs in moments, the sound of crackling raw magic following her as the violet fire seared through the darkness, trailing diagrams and words behind her like sparks. For Twilight it was like riding a wave of pure willpower: believing herself upwards, focused through the lens of the spell she'd crafted only moments before and amplified by her raw talent into the eldritch fire propelling her upwards.

She barely missed impacting the ceiling of the stairwell, diverting at the last moment to crash hooves-first through the door at the top of the endless staircase. Twilight rolled for a short while then tried to stagger upright, only to fall over from dizziness. She shook her head and stood up, clearing the cobwebs of dizziness from her mind with her determination to continue.

Twilight found herself in a large vaulted chamber, with the elegant architecture of Canterlot Castle alongside grim images of skulls and bones, accented by the actual skulls and bones that littered the floor. Twilight had never seen so many bones in one place, not even when she'd visited the Elephant Graveyard with the rest of the School for Gifted Unicorns, and the sight of so many so casually discarded made her stomach churn. From the far end came a distant glow, which beckoned the unicorn forward. As she approached, the light grew stronger, and Twilight had to stop herself from gagging once she saw what the source of the light was.

An enormous tank full of the dark fluid sat embedded in the far end of the room, inside which floated a huge glowing eye, that regarded Twilight with a kind of cold fury. The Warden of this place, she assumed, like Scum had been. The thought of Scum gave the purple unicorn a stab of guilt for a moment, but then Twilight stood before the tank, trying to ignore the way the floor crunched as she walked over it, “Let me through, Warden, and return the Warden Scum to me, I will not be stopped by your dark sanctuary!”

The eye widened a little, and Twilight was able to see that the light from within the tank was actually being shed by the portal embedded in the pupil of the eye itself. Strange runes glowed in the iris of the eye and words snaked into Twilight's mind without the courtesy of visiting her ears, Child of mortal flesh, the eye responded, Your arrogance will be your undoing, and you will pay dearly for bringing iron into my domain! Twilight had barely received the final message before the floor gave out from under her, and she fell far onto something firm but yielding that was moving quite quickly.

Twilight sprang to her feet, and found herself on a gruesome conveyor belt, with the hole she'd fallen through already gone. Bodies of all kinds of creatures, all still fresh, were being pulled along with her towards some lighted funnel at the far end from which the grinding chaos of the lower levels issued like a growling threat. Twilight barely had time to realize she was in danger until she was almost into the funnel herself, which, this close, she could see was covered in blades so sharp they seemed to liquefy the bodies that fell in, funneling the ichor into a churning pit of sharpened silvery blades.

Twilight quickly teleported back to the other end of the hall and focused on dodging between the corpses to keep from throwing up. A flash of movement caught her eye, and Twilight danced over the bodies and parts thereof to find Scum, still barely clinging to life and bleeding through the hole the hook that had taken him had made. Twilight levitated out one of the golden apples, which were still miraculously unharmed despite the thrashing she'd gotten, crushed it with a thought and forced it into his mouth. The wound closed, but Scum didn't awaken immediately, so Twilight picked him up with telekinesis and started fighting the current of the belt, dodging the dead and dying as she looked for the trap door she'd fallen through.

Twilight tripped, lost her control and dropped Scum, who woke up when he hit the belt and started running once he realized where he was, his eyes wide and terrified, his bloated-looking form pumping with hidden muscles to preserve his life.

Twilight used magic to skip around the conveyor belt, teleporting and telekinetically jumping around, but Scum had no such ability. Scum screamed piteously, but Twilight couldn't hold him telekinetically and dodge the macabre impediments in her path at the same time in such a dark environment. Finally, in frustration, Twilight focused and cast a raw spell, with no preparation at all, stomping her hooves, amplifying it and driving the corpses to the side, breaking the conveyor belt in the process. Unfortunately, the sudden stop sent everything flying towards the horrible flensing funnel, to the purple unicorn's horror.

Scum flew forward towards a terrible fate, and was actually over the bladed funnel when suddenly something brilliant appeared below him and caught the green former unicorn. Twilight had teleported beneath Scum in a moment of desperation and spread her limbs so her iron-shod hooves would impact the walls of the horrible funnel, easily crushing the silvery blades somehow. She had caught him, though she felt her hooves prickle with pain at holding him up in such an awkward position. Below, Twilight could see that the tube attached to the funnel was also coated with blades, in a spiral pattern that would quickly reduce anything that fell through into the ichor that sustained the Eye above.

She smiled weakly at Scum over her shoulder, and was about to teleport them both to safety when one of the horrible hooks from before snaked up and grabbed at her. Before it could penetrate, Scum had flung himself onto it, and screamed to Twilight in the instant before he was pulled down, “RUN!” Then the creature that had once been a unicorn was pulled through the bladed tube, and Twilight deeply wished she could forget that sight, and the sounds his painful descent made.

Something snapped in Twilight at that moment, she started to scream, and pink and purple flames limned her body, no longer trembling over a terrible fate, but shaking with fury as the unicorn was lifted by her own magical wrath. Words of fury and sorrow flashed around Twilight as for the second time in her life her magic took control. Beams of raw force smashed through the Red Bastion as she rose to face the Eye once more on a pillar of pure magic. The building screamed as the purple unicorn's violet fury found the very foundations of the Bastion and gripped them tightly. She glared at the Eye, which shook in its tank with fury and fear, slopping the foul ichor that sustained it over the edge of its tank.

“OPEN THE WAY.” Twilight hissed in a voice that reverberated through the cathedral-like space, and when the Eye didn't immediately respond, she crushed one of the foundations, causing the building to scream once more in a voice of tortured metal as the whole structure lurched in one direction. The Eye focused on Twilight and shook back and forth in clear denial, while more barbed hooks sprang from the hole in the floor on arms of silver. Twilight didn't even notice as they melted before they touched her, she just flew towards the Eye, tendrils of magic shooting through the glass into the portal in the pupil of the Eye, causing more screams from below, and the Eye to tremble in its tank, obviously in pain. Twilight's vision filled with red as she ripped the Eye from the tank and pulled herself through the portal along with her magic, eliciting the greatest scream of all from the stricken slaughterhouse. Once she was through, Twilight was enveloped in darkness.

Twilight awoke some time later on a book-strewn path in the comparatively cheerier surroundings of the Hedge. She looked around in confusion, “Scum? Blackboard? Where are-...” Twilight broke off once she'd turned around and spotted the crumbling, bleeding heap of rock, gore and metal that had been the nightmarish Red Bastion through the opening in the path behind her, lit by the midnight moon. She looked herself over, and found that she still had the apple baskets, which were still well-secured, and the purple unicorn's coat had been somehow cleansed of blood, though spots of soot caked her iron-shod hooves.

Scum was dead, she remembered dimly. She'd seen him die, his body ripped to pieces by the horrible machinations of the Bastion itself, but things got a little fuzzy after that. Strange, she'd been angry with Scum at first, torturer that he'd been, but now she just felt sad. He'd been broken by something in this place, and turned into a minion of it. Yet... At the last, he'd saved her, protected her from harm. Something in the rotted, insane husk of what had once been a unicorn had been concerned for her well-being enough to sacrifice himself.

The thought of what Scum had once been reminded Twilight that she couldn't linger, Applebloom was still relying on her to save her from similar madness. Still, she felt she should honor Scum's memory somehow and made a clumsy cairn out of books. She took a moment to use her magic to change the text on the cover, which had been gibberish anyway, to “SCUM THE UNICORN: THEY CAN'T TAKE EVERYTHING FROM US.”

Twilight stared at her work for a moment, then fused all the books together, changing them into solid iron with a transmutation spell. Then she took a deep breath and started down the path once more, putting her tears away for now, at least until she'd saved Applebloom.