A/N: This is an AU fic I've been wanting to do for a while. I'm a slow writer, so expect updates to also be slow, and I honestly doubt if I'll ever finish this – but it'll be a fun ride while it lasts. Since this is AU, several characters have been played with, taking on roles slightly different from their canon counterparts (with Ruby, of course, being the major one). I've also taken down a peg Aura's defensive capabilities; it's probably easier to animate the same models over and over, but it makes for boring writing.

My biggest worry is that this fic becomes completely invalidated by canon, e.g. if they make Neo talk.

Chapter 1: Heist

The train wound through the valley like a snake. On both sides of the tracks, mountains jutted upwards at almost right angles, topped with dense maple trees that had turned blood-red with the season. Hidden among the leaves, concealed further by a red cloak, Ruby listened to the ring of the steam-whistle rise to a roar. The train will soon arrive at the ambush point. She took a deep breath.

"Alright, Neo. You ready?"

Next to her, the girl with pink-and-brown hair rolled her eyes.

"I was just asking," Ruby said. "Let's go."

She slid down the mountain slope kicking up a cloud of fine red dirt. The wind blew her hood back, tossing her hair behind her. Familiar to her was the thrill of the hunt, a cocktail of nervousness and anticipation in equal measure, and she had to laugh even as her laughter was swallowed by the roar of wind and steam-engine. Two-thirds of the way down, she vaulted forward, crashing onto the train's roof so hard she had to drive the point of her scythe into the metal to prevent herself from being thrown off. Neo, on the other hand, landed gracefully as a ballerina, umbrella cocked over one shoulder.

"Show-off."

Neo smirked.

They found the entry hatch two cars ahead. Ruby braced her scythe against the lock and pulled. The hatch popped open, revealing a mouth of darkness. She jumped down.

Right into an army of robots.

"Oh, come on!" Ruby said. "Mercury never said anything about this!"

The machines whirred to life. Atlesian Knights, judging by the shape of their helmets, and not old models, either. Each one stood six feet tall, chrome armor polished to an unblemished sheen glinting under the enflamed light of their faceplates. Their chests bore two insignia Ruby was intimately familiar with – a snowflake, and a torch inside a gear. Before the two of them could rise, a dozen Knights had already surrounded them, arm-blades extended.

"Intruders, identify – "

The bullet smashed its head to pieces. The wires poking out of its neck crackled and darkened; the Knight fell forward.

The other Knights looked at each other. Ruby could practically see the gears spinning inside their metal craniums, running through combat protocols. In that span of indecision, she had swept half the room, firing off six more shots that left her ears ringing in the cramped space. Six dull thuds as six metal bodies hit the floor.

The Knights reached her before she could fire her seventh. She brought Crescent Rose in a sweeping arc, the music of sharpened blade singing through stale air, and two Knights became four, bifurcated on the train floor. The third Knight slashed forward with both armblades, found purchase in nothing but a shower of rose petals. Ruby reappeared behind him, her scythe notched against his neck. She pulled the trigger; the bullet pierced the ceiling as the recoil severed the Knight's head. A lonely ray of sunlight fell through. The two remaining Knights came at her from both directions. To her they might've been moving through a film reel, one frame at a time. She dodged the right slash, dodged the left slash, then spun on the ball of her foot, swinging Crescent Rose through a full three-sixty-degree arc. The legs of the two Knights remained motionless on the floor; their upper halves toppled over.

Ahead of her, Neo had taken a seat on a crate. She crossed her legs and yawned.

"Thanks for the help," Ruby said.

Neo shrugged.

"What do you mean, it's not worth the effort? Well, I guess they were rather easy," Ruby said smugly. She shook her head. "Anyway, we need to set the charges. You have them, right? – okay, that was a dumb question. Let's see, we're about halfway up the train, so all the cars behind us are carrying cargo. You set the charges. I'll – "

A metallic roar echoed from above. Ruby jumped back just in time to avoid being crushed by the eighty-ton Spider Droid that how the hell did she not see that thing? Atlas's cloaking technology must be further advanced than they thought. Ruby made a note to hit Mercury on the head with her scythe the next time they met. The thing was as large as a tank – the train trembled with its steps – striped red and black like a tarantula, its upper body nothing more than four massive canons supported by four equally massive legs. For all its size, it had a flowing quality to it, moving with smooth, agile steps reminiscent of its namesake. An unknown prototype, then, and it looked like Atlas had managed to iron out the kinks with the known ones. Ruby grimaced. A single hit by one of those Dust-amplified canons would be the end of her. She stepped back, holding Crescent Rose in front of her like a shield. Next to her, Neo had stood up, eyes narrowed.

"We don't have time for this," Ruby said. "We need to detonate the charges before the train reaches the checkpoint. Oooh, if that happens, Dad'll be so mad! You go! I'll hold it off."

Neo hesitated. She looked at Ruby, biting her lip.

Ruby smiled. "I'll be fine. Trust me, sis."

Neo sauntered forward. The box car was cramped, the Spider Droid looming over the entrance with its body scraping against the walls. One moment it was motionless. The next moment it had shot forward, striking out with its leg like a scorpion's tail. Neo blocked the strike with the point of her umbrella, using the momentum – surely that had to break a law of physics somewhere, Ruby thought – to vault over it. The Spider Droid's upper body rotated, its canons tracking her movement, heating up with a bright blue light. The bullet plinked off its head. Ruby fired four more times, listening with dread to the dull, hollow echo of her bullets bouncing off its armor. But it was enough. The Spider Droid turned back, its single red eye zeroing on her.

The supercharged plasma beam swallowed the length of the car. Ruby managed to avoid it by pressing herself against the wall, but even still the heat left a scorch mark across her chest, white with pain. The beam blasted the far wall completely open, revealing a landscape of crimson trees and crimson skies, passing by at blurring speed, and the sunlight on that cold autumn morning was so bright Ruby was momentarily blinded, missed the Spider Droid's leg that smashed into her side hard enough to send her careening through the opening. She landed in open air. Something crunched in her abdomen. Shakily, she picked herself up, watching her coughs splatter blood against the train platform. She heard a high-pitched whirring, like a gyroscope spinning faster and faster, and that was enough; she threw herself to the side as a second blast tore through the air.

Red leaves swirled around her. The Spider Droid crawled forward. The steam-whistle blew three times, signaling the train's imminent arrival at the station. They were almost out of time – and so was she. The Spider Droid's canons lit up for a third blast.

Gently, Ruby unclasped Crescent Rose's magazine and replaced it. She held her scythe hilt-forward, shaft tight against her arm, blade braced against her back.

The beam tore through her, but she was no longer there.

She surged forward on the crest of a rose wave. Her first strike glanced harmlessly off its leg. Its other leg lashed out at her, but she was gone again, driving the scythe-blade into the crevice between its arms. She felt something give. She pulled the trigger, letting the recoil drive the blade forward to slice its arm clean off. The screech of breaking metal might've been a screech of pain. The Spider Droid swung around, firing off a blind blast that left a hole on the platform floor through which she caught a glimpse of tracks rattling by. She appeared next to its leg, the barrel of her rifle positioned in front of the thin crevice between its armor plates. The bullet tore through the joint as easily as if it had been made of bone and flesh. The Spider Droid tilted over. Her third strike cleaved through another arm, her fourth through another leg, her fifth finishing off both arms, and by this point it was no longer a challenge. The Spider Droid stumbled, barely upright. She appeared one last time riding its shoulders, the blade of her scythe hooked around its torso, and pulled the trigger. Metal groaned. Her scythe dug an inch further. She fired again, and again, and on the fourth the Spider Droid's long-suffering armor at last gave away, and the scythe-blade cleaved through its body with a noise like splitting thunder.

She dismounted and sank to one knee, gasping. Her vision was fuzzy – the first sign of Aura exhaustion. When she pressed a hand against the spot where the Spider Droid's leg had smashed her, her fingers came away red. Using Crescent Rose like a walking stick, she pulled herself upright. The air was brisk, ripe with the smell of coal as the train's engines carved a trail of steam through the sky. Around her scattered the dissected parts of the Spider Droid. In the distance, Neo was racing toward her, eyes wide with fear.

"Charges are set?" Ruby asked.

Neo glared at her.

"Oh, don't give me that look. I'm fine – "

Neo poked her finger at Ruby's side.

"Ow! Okay, I'm not fine, but I'll live, and it worked out in the end, right? Anyway, we have more pressing problems at hand. You set the charges?"

Neo jerked a thumb over her shoulder.

"No, we can't leave yet. The job's not over."

Neo gave her a disbelieving stare. Ruby staggered to the edge of the platform, where the chain-link coupled this car to the next. She broke the link with Crescent Rose. Immediately the platform shifted beneath her feet, almost sending her over the edge had Neo not been there, holding onto her arm with a slim hand. Wheels screamed against the rails. The platform ground to a halt as the cars ahead of them – full of crew members – pulled further and further away.

"Now we can leave," Ruby said.