Story co-authored between Omicron the IceQueen and Ultra Rodimus!

Queen's note: Fear the products of boredom that the two of us have come up with. D Anyways, I just wanted to point out a few things, one is that both the Transformer and Bioshock worlds depicted here in this story are AU from canon, being of Cy's sagas and my own interoperation of Rapture for stories I'm working on. The first few chapters are a bit rough as we were experiencing and I was settling my new character.

As to my Jack, I named her that at random by going through my dad's cell phone contacts XD it wasn't until a week or so later I realized the name similarities between her and the Jack of the first game. Also, size ways, Jack the girl only comes up to Ulti's lower thigh, and I'm assuming that he didn't know how old/young she was because Ulti doesn't have a lot of experience with humans yet here. Cy can confirm in her note

Cheers!

-Icy

Ultra Rodimus's Note: I had quite a bit of fun working on this, watching how Ultimus adjusted to Rapture, and how Rapture deals with him. Ulti is taking it pretty well, while Rapture in general is not sure what to make of this new metal creature roaming its halls. This story is also separate from my own fic series; this is more of an AU spinoff than anything directly attached to my fanfic series, the product of boredom more than planning.

No less fun for that, though XD

Ultimus is learning the world of Rapture as he goes; he came into this world completely clueless and has to adjust fast. Fortunately for him, Cybertronians are an adaptive breed, and he's no exception.

Into Rapture

Light.

Sound.

Wind.

Disorientation.

Ultimus covered his ears, squeezing his eyes shut, trying to block out the sound and the light, but it was fruitless. So this was a dimensional rupture.

Not long after, he was spit out, landing on a hard surface hard enough to knock the wind out of him. That was enough to let him know that, like his commander, he had changed form. He lay still for a long moment, getting his scattered thoughts together. He heard the sound of dripping water, of faint yelling and heavy footsteps. There was the smell of seawater and death, dankness and rot. Finally picking himself up, he looked around.

It was a dimmed room, lit only by a fading yellow bubble above and looking like a turned over storage room. Supplies here and there, and the ground under him was metal plating as well as the walls. There was something that smelled sickly sweet, coming from beyond a few shelving stands.

Groaning softly, Ultimus climbed to his feet, wobbling slightly as he got his balance back. A quick check of himself revealed some interesting bruises under the featureless jumpsuit he was somehow wearing. Once he felt steadier on his feet, he made his way cautiously toward the strange smell.

There was a splattering of red-brown out the ground and, after rounding a cabinet, the human formed Autobot would see a door, partly open. The trail of red led into this smaller side room, and if the door was opened something rather unpleasant would fall out.

Ultimus eyed the smears, then inhaled slowly, nostrils flaring. It smelled like blood, but there was something weird about it. He sidled closer, hooking one foot into the door and kicking it open before leaping back. The thing that had once been a body... splatter down, breaking apart partly. The smell increased now that the body was in the open, and there was something off about it beyond the decaying state.

The redhead eyed the body, remaining a distance away. It looked to have been human, but looked strange. He sneezed at the smell, backing away, circling it at a distance.

"Hmm, mmm, hmmm!" A soft, and muffled voice filtered in from the background sounds, that thumping from before increasing as well. A child's voice spoke from outside another door, "ADAM Daddy, this way! I can smell it."

Ultimus's head snapped around, fixing bright yellow eyes in the doorway. Even in his human form, his eyes glowed in the dark, twin yellow lights in the dimness. He backed away from the body, into the shadows, watching.

The door cycled open, sliding upwards to reveal a small form, shadowed by a much bigger frame that couldn't make it through the door. A childish giggle came from the smaller one and a young girl back up into the store room, looking at the big form outside.

"Don't worry Mr. Bubbles! I can get the ADAM," She said, and coming into the yellow light her worn, stained dress became visible. Her hair was pulled up and tied with a pink ribbon, she was bare foot and had almost too pale skin tone.

Yellow eyes narrowed. Ultimus's sense of smell brought him the scent of old blood and something else, something inhuman. The shape outside smelled of gunpowder, blood, and salt water. Whatever it was was just outside his field of vision. Settling into his corner, he watched.

The child was human, or looked it at first. As she turned her own slightly glowing eyes, shined over with yellow were visible. She scanned around, sniffing at the air before walking straight for the corpse. She lifted a device in her hand, a thing that had a handle, long needle, and a bottle. "I smell ADAM...ohhh there's roses!" She added spotting the bloodstains and other liquids.

Ultimus eyed the child, wondering if she was high on something. He'd only heard talk like that from stoners and druggies he'd heard in dark alleys. And what could make her eyes glow like that?

The girl padded closer, still sniffing until her odd eyes landed on the corpse near the Autobot. She smiled and brightened up, "There is an angel in here Daddy!"

A deep vibrating rumble came from outside in answer as the child walked unfazed through the slushy, sticky remains. She dropped down to her knees beside the corpse, lifting the extracting needle as she eyed the remains carefully, "I see it! It's glowing it the belly." She stabbed down and compressed the trigger, glancing around as she did so but didn't seem to really see what was around her.

Ultimus' eyes glowed in the dimness on the far side of the room. Quietly, flesh shifted to metal, hydraulics whining softly as he shifted position slightly. The double, curved horns cresting his helm cast an odd shadow on the wall behind him. He remained still, otherwise, watching from a distance.

Humming tunelessly, the girl continued her work, pulling the needle back and stabbed back down to change the angle. The bottle at the end was filling up with reddish liquid, blood and something else that glinted not quite naturally in the dim light. She truly didn't seem to notice anything around her as she... worked.

Ultimus inhaled deeply and slowly, sorting out the scents carried on the air. The reek of blood was overpowering. Normally, the smell of blood would waken his own hunger, him having fed on the blood of his own kind for eons, but this stuff smelled of something strange and potentially dangerous. Staying where he was, he watched, allowing the air to hiss out of the vents of his neck and shoulder armor.

There was another rumble from outside as the girl finally stopped. She peered at the bottle and nodded, standing up, and moved to lift the device up to her mouth. Yellow optics flashed, then narrowed. Something weird was going on here. The focusing lenses in his eyes narrowed in on the girl, wondering what was going on.

She started to drink as if downing apple juice, gulping down the blood mixture until it was gone. She coughed and wiped off her lips with one bare arm, "All done!" She turned starting to smile but paused, the smile fading as she looked around, "Mr. Bubbles?"

Ultimus stayed where he was, a vague shadow with glowing yellow eyes, fangs glinting dimly as his lip curled back from his dental plate. What was going on here, and what was this place?

The girl's own eyes finally saw the optics and brightened, with the main door closed now she focused on the mech, "Daddy!" She said bouncing closer and holding up her arms, "I'm all done!"

Ultimus let out a warning rumble, moving away from her. He paced along the wall, wondering what she was talking about.

"Daddy? What's wrong? I got the ADAM, I was a good girl." The child said, frowning in confusion at the retreating mech.

"I am not your daddy," he rumbled in response, showing fangs. "Who are you? What are you?"

"Not...Daddy?" Her eyes widened and she took a deep breath, not picking up the pheromone anymore she backed up, hugging the extractor to her chest like a normal child would a favorite, comforting toy. Programming kicked in and she gave a scream before turning and running back to the outside door. At her scream there was an answering roar from outside.

Ultimus remained in the far corner, just standing there, optics narrow. He leaned against the wall, just watching, maintaining his distance.

The girl didn't look back as she darting outside to the bigger form in the darkness, crying out. "Bad thing Mr. B! Bad thing!" She was grabbed up and the monster outside retreated to her yell. Faintly there was a yelp heard and another roar before someone else stumbled into the room.

"Holy crap!" The form yelled and lunched to the side before flattening herself against the wall so not to be seen.

Ultimus quickly moved, getting between the woman and the door. His eyes glowed brightly, and he showed fangs. "You. Talk." He advanced on her, keeping himself between her and the door. "What is this place? Who or what was that girl?"

"What the- another tin daddy?" The woman's eyes widened behind her mask made of sticks and twigs as she realized there were spoken words. "Aw crap! I didn't hurt that Little Sister! Honest!"

Ultimus moved into the light, revealing hair the color of a fire's heart and bared fangs under a vaguely Roman-style helm, crested with hornlike curves of glittering metal. "Do I look like one of those 'tin daddies'?" he growled. "What the slag is this place?"

The woman tried to squish herself more against the wall, "It's Rapture! The same old city at the bottom of the freaking sea!"

"Never heard of it. But being under the ocean would explain the smell of seawater and the constant sound of dripping." Ultimus's lip curled. Yellow eyes narrowed. "Who was that girl and what was that thing that took her?"

"That was a Little Sister- ADAM factories they are." The human said, shaking from tremors of real fear. The only thing she could link the mech to was a Big Daddy after all. "That was a Big Daddy. They're the guard dogs of the girls."

"What is this ADAM?" he demanded, leaning closer. Air hissed from the air vents on his neck. He inhaled, taking in the woman's scent. It was every bit as strange as the corpse's and the girl's.

"ADAM is ADAM..." She said, not sure if she was happy or glad her shotgun was laying out in the hall. "Makes the world great... it makes and fuels Plasmids."

Oh, that's right she had plasmids!

"Plasmids," he repeated, wrapping his tongue around the strange word. "What are plasmids?"

She debated something before lifting her right hand and flexed her hand, mentally triggering her Incinerate! plasmid. Veins of red came to life around her forearms and hands. "Like this."

The redhead regarded the red veins with what appeared to be a mild curiosity. "Is that supposed to mean anything to me?"

The far shorter human snapped her fingers and fire erupted between them, another snap had the fire larger, "Plasmids, strange tin daddy, are this." She grinned under her mask, getting some confidence back with the use of the Plasmid and rush of EVE in her veins.

Ultimus regarded the fire with interest. His armor was resistant to fire as well as to extremes of heat and cold, for the most part. He brushed red hair back, then casually stepped into the flames, using it to burn off some of the fluids that had gotten onto his armor but otherwise taking no harm from it. "Thanks for the armor-cleaning." He gave her what could have been called a grin if it hadn't revealed his fangs so well.

There was a pause and then, "You're... welcome?" the woman... no, the girl offered, voice squeaking and now showing it was younger than first thought to be.

The mech brushed bits of ash from his shoulder joint casually. "I'm not one of those 'tin daddies' or whatever you call them. I'm something entirely different and something even worse if you piss me off." He lifted one hand, and it was suddenly resting on the hilt of a broadsword with a blade at least five feet long, the edges razor sharp.

The human made an interesting sound before sagging against the wall. Giant non-Big Daddy but Daddy like in a way, and things popping out of nowhere like it really shouldn't on top of her scares earlier... She needed a temporary break from reality.

Though the mask did get in the way to see for sure that she fainted.

Ultimus looked at the crumpled female for a moment, turning her over with his foot. He eyed her for a long moment, and then walked toward the door, sheathing the sword across his back as he did so. Ducking slightly to make sure his helm crest cleared the door (he was nearly eight feet tall by himself, and the crest cleared eight foot three), he stepped out into the corridor.

It wasn't much different, other than it had at one point had wooden paneling. A few puddles of water were here and there. To the right was another fresher body, one that was probably anywhere from a few minutes to a few hours old, so that the gross comedic mutations were visible.

The redhead inspected the body, taking in the mutations. Then he turned and began walking down the corridor.

"Uuuggh, bloody hell this isn't my day." The human from before said as she staggered out of the store room, pushing up her mask to run a hand over her face before sighing deeply.

"Apparently not," Ultimus' basso rumble echoed from slightly farther down the corridor, and yellow eyes glowed at her from a shadow not far away. He was inspecting some old wiring hanging loose from a wall, pulling a piece loose and snapping it like a whip.

The woman jumped sideways, her hand reaching out over her right shoulder. But she grasped at air as her shotgun was several feet away and not in the rigged up holster. "Gah!"

"It would only bounce off my armor anyway," he informed her calmly. "No human weapon can harm me."

"There's still splicers around!" She said, grabbing up her trusty modified rifle and checking it over. "You got a name tin daddy?"

"Ultimus," Yellow eyes glowed brighter. "What are splicers?"

"That." She pointed at the dead corpse with the shotgun before reaching up to pull her mask back into place.

Ultimus regarded the corpse dispassionately. Then his gaze returned to her. "What's with the mask?"

"Camouflage." The woman said shrugging, "Most Splicers had a mask to hide their mutations. Like this I can get away from most of them."

The redhead cracked his makeshift whip, stripping off the insulation to expose the bare wires at the end. He wrapped the other end around his hand. "And why are they called splicers?"

"From too much gene splicing with ADAM and plasmid," The woman said, eyeing the mech through the mask's eye slits, "You really shouldn't be messing with that stuff, the Thinker may overload it."

Ultimus held up the end, showing that he'd already detached it from the wall. "Who is this Thinker?" He glanced around, and then narrowed his eyes. "I have no idea of the layout of this place." Yellow eyes slid back to her.

Her back stiffened as the human back up and away, "Oh no. No, no, no..." The human shook her head, "Oh my! I think I hear a Big Sister! Bye!" She turned to bolt down the hall.

Metal shifted and changed configuration. It was a four-legged form that raced after her, leaping over her head and landing in front of her. Yellow eyes pinned her over bared teeth as the metal wolf, standing easily as high as her waist, blocked the corridor ahead of her. The human let out a scream, having lived her whole life in this underwater city. The only non-swimming animals she knew of were either a bird, insect, rats and house cats that were brought down or hitch-hiked. She let loose a fireball in reaction, scrambling back on the ground and holding onto her shotgun in a white knuckled grip.

The fire washed over blue and gold-marked armor, not even singeing it. Ultimus transformed back to robot form, looking down at her from his full height. "Going somewhere?"

The human said some very bad words and then, "What the hell are you?" She said, mask ajar so she had to shove it upwards to see, "What in the sea was that you were?"

"I am a Transformer." His eyes flashed at her. "And my other form is a wolf... A large and powerful carnivore."

"Wolf?" The girl asked, confused at the word but managing to stand and put some distance between her and the mech.

"Try to run, and I can track your scent anywhere," he informed her flatly. "I'm a predator as well. And your scent is rather distinctive."

"That cuz' I was almost a Little Sister." She said crossing her arms as best she would holding a rifle, "Got everything but the slug and brain washing."

He bared fangs briefly. "I know nothing about this place or anything in it. If you think I'm going to let a source of information just run away from me, you're out of your mind."

"You know there is such a thing as asking nicely." Even if it didn't happen that often it was a lot nicer than being scared into flames more than once.

"Somehow I doubt that happens much in this place." His gaze bored into her. "Will you behave this time, or do I have to make a leash?"

The woman hissed at that and jumped backwards, she glared and then turned around, "Fine, whatever I'll play tour guide. But you'll have to help out in the mean time." She said, sliding her shotgun into its home made holster on her back before fixing her mask again.

Rapture was a big city, this weird person may get lost if she was lucky.

He reached back to tap the sword hilt showing over his shoulder. "I don't respond well to being attacked, at any time."

"Neither does anyone down here." The human said as she walked to the dead splicer, "More so the 'normal' adults and Splicers. The Big Daddies and Sisters really get pissed."

"As I said, I'm like nothing else down here. You don't want to see me when I get really get angry." He paced along after her, uncannily silent for his size and weight, as well as for his steel boots.

"Yeah, I gathered that tin daddy." She shrugged and knelt down by the body, reaching into the tattered jacket pockets and came up with a wallet and several shotgun casings, "Oh nice, ammo."

Ultimus watched, sweeping out his own sensors along the corridor. "Nothing alive of any kind detected anywhere near us."

"That's good and bad," There was a pause as she stood up, "Name's Jack." She said looking at the mech, "And when we do get to more populated areas, you're going to have packs after you."

"I gave you my name already. It comes from 'ultimate warrior'." His eyes narrowed. "I've faced worse odds in the gladiatorial arenas."

"The what, in what?" Jack tilted her mask head, "Never heard of them." She kicked the dead splicer before moving away. "I was heading to Arcadia for some better food. There's a tram ride if you want to see the city."

"The arenas? People like me were made to fight and kill each other in bloody, violent fights, to entertain those who had enslaved us. The fact that I survived is proof of my own skill." He growled deeply for a moment.

"Why would anyone what this," She waved her arms, meaning everything about her known world, "For entertainment?"

"Those who enslaved us forced many of my kind to fight to the deaths for their amusement. More were sold as slaves. When we got fed up and kicked them off, it was a very bloody rebellion. They were sick creatures." Fangs flashed in the dim light. "Those gladiators who didn't kill their opponents bloodily or slowly enough were often tortured to death later."

"Sounds like Sander from Fort Frolic." Jack sniffed in distain from both her own experiences in that place, as well as inherited memories before walking again. "Glad I got out of there, one thing the Little Sister Program did for me I liked."

Yellow eyes gave her a look, a scarlet eyebrow lifting in a silent question, "Little Sister program?"

"Right, hang on. Rapture 101," Jack said and she motioned for Ultimus to follow her to the side of the hall. She looked up and down and aimed a kick at a panel; it shuddered and lifted as it was dislodged from a light lock. Jack stepped back to watch it rise and a pale blue glow filled a little section of their hall. "Other than we're at the bottom of the sea."

The mech followed her in a strangely silent trot. "There is nothing like this where I come from."

"The surface world doesn't really know about us." Jack shrugged. "Ryan made sure of that. He's the one that started Rapture. Anyways, down here science wasn't held back in anyway, and one of the many breakthroughs was ADAM. It could change our DNA, refined it into plasmids." The woman held out her arms, the red veins flashed before vanishing and blue pulsing veins replaced them, energy skipping between her fingertips.

"And these plasmids give you different powers, I take it." Ultimus eyed the veins. "Why would anyone want to live at the bottom of the sea?"

"To get away from the surface, the wars up there, the government." Jack shrugged, "I've lived down here my whole life, all twelve years. So I don't know everything that the adults wanted to get away from. But for as bad as it is down here, it's supposed to be worse up there." She pointed up, and from earlier when her mask was off she had looked closer to her twenties...

"From the look of things, it's far worse down here than it is up there." He glanced around the corridor. "I for one am quite addicted to seeing the sky. But then, I am a flier, and I need the sky."

"Fly?" Jack looked up with a confused expression again, from the few pictures she'd seen and the lessons she had. How big and empty the sky was supposed to be... She shuddered at the thought, "I'd never do that, too much space, you may fall up and there's not supposed to be much in the sky so you can't swim to safety."

"Fall up?" Ultimus let loose a bark of laughter that made Jack jump, "Gravity holds you bound to the planet; you can't fall up. Unless you're flying fast enough to break through gravity's pull. The sky is open and wide and beautiful, and there is nothing like the feel of wind rushing over your wings, seeing the earth laid out before you." Panels on his back shifted, unfolding to reveal pointed, sleek wings.

The young woman (or was she really a child?) reached up to lift her mask up, finally willingly coming closer to Ultimus more than eight feet for a better look. "You really don't fall up?" Jack asked, confirming a bit that she was younger than first impression.

He shook his head. "No. You can't fall up. The planet pulls you to it; you can fall down, though. But falling up is impossible." He turned slightly to show off his wings. "There are engines in my legs; when ignited the exhaust can burn flesh from bone. I have seen cities and forests and miles of open fields spreading out before me, from over thirty thousand feet in the air."

"Cities like Rapture?" Jack glanced at the window, but realized there wasn't a really a view of the city line at this angle. They were on the outer end and facing the wrong way. "And... forests are bunches of trees right?"

Ultimus turned his head slightly. Thin beams of blue light lanced out from his eyes, forming a three-dimensional image. A great city rising from the earth, spires reaching for the cloudless blue above, vast forests, birds glancing over as he streaked past, dancing among puffy whiteness, fields overrun with a rainbow of flowers.

The girl hopped and jumped away from the holograms, startled and started reaching for her shotgun but froze. Jack stared at the image as she slowly became transfixed, "...that's the surface?" she breathed, eyes wide as some instinct or inner need reached out.

"This is the surface world." He changed the image again, this time showing a sky aflame with vivid reds, oranges, yellows, and purples as the sun dipped below the horizon, the moon rising from another angle into a sky spangled with glittering points of light.

Jack's fingers passed into the image, trying to touch the moon, "I've never seen anything like it... not even the Arcadia domes and those are the best place in Rapture sometimes."

"There is very little that can compare to watching the sun rise or set, feeling the breeze on your face, seeing the grasses rustling and waving around you," the mech rumbled.

The girl was about to say something, maybe, but didn't get a chance as there was a thump from outside the window. Jack turned, taking in the upside down, lean form, the glowing orange porthole and shape of the helmet- as well as the attached needle/blade... Jack did what any sane or semi sane person would do, or at least those who knew of this brand of Rapture's living nightmare.

She yelped and tried to hide behind Ultimus' leg.

The mech bared fangs at the shape, but did not strike; shattering the window would only flood the area

The figure didn't move at first, just staring at the Autobot's leg where the girl was behind.

"Big Sister!" Jack hissed, trying to be small. "I'm not here- Don't tell her! I don't want to be a Little Sister."

"It's outside," Ultimus rumbled in response, shifting his wings to a position that displayed aggression.

"They can teleport," Jack said, "They've absorbed so much ADAM and plasmids over the years, but..." She paused and then realized something, "They don't travel alone anymore. Not the younger ones anyways."

"I'm no teleporter, but I'm a veteran warrior with quite fast reflexes and very thick armor." Ultimus scanned the corridors again. His scan would have picked up something new, something that had been quietly walking in the darker part of the hall towards him and the human. With the same lean figure as the one righting itself in the window, but crouched low and the portholes dimmed to a dull glow so not to attract attention.

Ultimus' head snapped around, and this time it was a harsh snarl that echoed down the corridor. A tooth-grating vibration started up, apparently coming from the backs of his legs. He bared fangs at the shape, wings arching into a definitely threatening posture, at least for anyone who could read the language of wings.

The newcomer froze, standing perfectly still as it took in the new sound and vibration. The dim porthole lit back up and turned a more golden hue. The second Big Sister still didn't move, but a low grumbling came from its helmet.

The mech lifted his hands, unsheathing a formidable-looking set of curved claws from his fingertips. He turned his head slightly to keep an eye on both of the Big Sisters, this time releasing a full-throated roar of challenge, a battle cry that had terrified his opponents in the ancient arenas.

An audio-piercing shriek came from the sister inside as well as out at the roar the sound rising high above the Autobot's tone. With a frame as lean as it was, the Big Sister's scream should have been nearly as loud as it was, making many things spark. Debris lifted up around the ADAM hunter inside, her porthole though remained the same color as she bounded forward.

Three paces and then she vanished in a purple mist, her scream fading away.

Tbc...

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