Prologue

"Tempest Tomahawk!"

A massive battle axe cleaved through the air, the resulting wind strong enough to slice through multiple massive Grimm that were in its path. The wielder of said battle axe was a massive humanoid machine, its face lacking a mouth and nose, that wore a white cloak over its head and body. Proportionally, it was certainly bulkier than the average person but that was simply due to its nature as a machine.

The pilot of this great machine looked to a screen on her left as it displayed multiple enemies approaching from her flank. The robot turned its head with its pilot as she let loose another battle cry.

This machine's name is Aura Rose.

"Silver's Gleam!" A flash of white light shone from the eyes of the machine, unleashing a power that turned all Grimm caught in it to stone. The attack was followed by the machine's battle axe shattering each petrified Grimm after being thrown.

The pilot let out a breath, a visible glow behind her helmet visor dulling as she heard the communication device in her helmet buzz to life.

"What are you doing?! Get out of there, you're vastly outnumbered with ZERO reinforcements coming!" A voice she knew all too well called out to her over the comm device.

"There was no time, Doctor… everyone else is either missing or too unwell to pilot," She said into her mic, suddenly hitting a pink button as she felt the ground rumbling beneath her machine, "Open Get!" The humanoid robot, incapable of flight, suddenly split into three jet-like machines that flew up into the air to gain altitude. Only one was manned, the other two set to an autopilot function. The one being piloted was white with red highlights, the second was black with red and white highlights, and the third was a dark shade of orange with brown highlights.

"Change, Aura Corvid!"

The three machines converged into one place at mach speeds, then proceeded to collide midair at specific angles. The lead machine was the black colored one, followed by the orange colliding with it from the rear, and then the white colliding with the rear of the orange. A long black cloak extended out of the black machine as it morphed to reveal a Grimm mask in the style of a Nevermore. The cloak obscured the rest of the body as it transformed, and red lightning briefly crackled around its form as it flew through the air at supersonic speeds.

"Tch, no idea how Qrow and Raven could control this thing so well!" The pilot muttered, struggling to accurately turn while moving at such high speeds. The ground where the machine was once standing exploded as multiple giant worms erupted from the ground. Grimm Sandworms, a nasty way for any pilot to die. The pilot slowed her machine to a stop as she commanded it to attack.

"Shrike Shower!"

From beneath the machine's cloak came a cloud of spikes that headed right for the Sandworms, each projectile exploding on contact and kicking up a massive cloud of dust and debris.

"And anyways, SHE is here," Muttered the pilot, staring hard into the smokescreen, "If I could hit her with a full power Silver's Gleam…"

"Then she'd be out of commission for who knows how long… I understand," The voice on the other end of the comms finished, "Her forces would be too disorganised to do anything as well."

"Exact-" She begins, but is interrupted by a barrage of sharpened feathers that pierced through Aura Corvid's cloak and into its body. A flock of Nevermore had managed to sneak up on her while she was focused. The Super Robot plummeted to the ground, its flight mechanism pierced by a massive feather and, unfortunately, so was the combining mechanism.

"Dammit!" Came the voice of the pilot as she collided with the ground, nearly hitting her head on the controls of her machine. She spit a globule of blood at one of the screens that blared on about the damage done, "Tell Tai I'm sorry, but this is the only way to keep her from invading and destroying everything we've worked towards," She directed to the mic as she looked around at every status report to see which weapons still worked.

"And what of the children?"

"Just," She starts, then takes a breath as she forces the machine to stand, "Just tell them that things didn't go as planned, and that I'm sorry."

Aura Corvid reached into its cloak, then held out the weapons hidden within. In one hand it held a red nodachi and in the other was a single edged greatsword. Final Omen and Last Harbinger. The machine ran through the smoke at speeds rivaling its air speed, spotting figures using its targeting system and attacking each with slashes that either set them aflame with Final Omen's fire dust blade or simply cleaved cleanly through with Last Harbinger.

"I understand, Summer… but what should I tell Ozpin?"

"That I bought him some valuable time, Doctor."

The line went silent as she stepped in a strangely soft part of the ground, and her eyes widened as she realized just what it was. It was too late for her to react as a large Deathstalker burst out of the ground, its pincers clamping onto Aura Corvid's arms as it drove its golden stinger through its proverbial gut.

"Damn it all! OPEN GET!" Summer shouted as she ejected her part of the machine from the two that were stuck due to the Nevermore feathers. She had been piloting from the legs portion this entire time, which turned into the jet-like machine as soon as it was free. The two others were crushed and destroyed by the Deathstalker, a necessary sacrifice in order to escape. As she flew up into the air, she managed to exit the dust cloud and finally see her enemies once again.

On the ground, and emerging from it, was a legion of gargantuan Grimm. In the air was a massive whale-like Grimm that completely dwarfed anything previously recorded. Such a congregation had to have taken quite a long time to produce from the Grimm pools of Salem's domain, which meant all the more if she could decimate it all here and now, but without the ability to fully form Aura Rose… she would have to take a leap of faith.

"Summer-" Came her comms once again, but this time she ripped off her helmet and tossed it to the side, revealing her silver eyes and red-black hair. Her gaze burned with the fury of a thousand suns as she began focusing, dodging every airborne Grimm by a hair as she made her way to the whale at maximum speed. Once she got within a certain distance, she was clear of most enemies, and as the whale opened its mouth to release another swarm of flying Grimm, she transformed her machine into the head portion of Aura Rose.

"Silver's Gleam!"

The mouth of the monstrous whale was stuck open, partially petrified, and the oncoming Grimm all plummeted to the earth below due to their frozen state. The jet changed back as it flew straight into the mouth and then turned upwards.

"Thorn Tomahawk!"

A large battle axe shot forth from the front of the machine which she followed up with lasers and machine gunfire, tearing a hole into the roof of the creature's mouth as it rumbled and screeched in pain. At the same time, Summer input a series of commands which started a visible countdown that took up every screen. She reached behind her and grabbed the white cloak draped around her pilot seat, putting it on and pulling up the hood before grabbing something else.

As soon as her jet collided with something, the windshield of the machine shot open and the momentum sent Summer flying up into the air. Within a split second, she assessed the situation and knew she was exactly where she needed to be when she saw the pale white skin of a corpse marred by the black veins of corruption. That had to be Salem.

Their gazes met, and Summer fell to the ground, but not without taking action.

"GYAAAAAAAAH!" Summer brought her battle axe down with as much power as she could muster, gravity aiding her as she split Salem straight down the middle. Whatever small victory she felt was quickly extinguished as the witch regenerated before her very eyes.

"Hm, how quaint," Was the witch's calm reply, "What did you hope to accomplish by coming here? You cannot kill me, so you cannot defeat me. Its all hopeless, so just give up and this can all be over."

Summer took a breath as she looked up, summoning every ounce of her willpower for what comes next.

"We don't have to kill you to stop you," She began, her silver eyes beginning to glow, "and we WILL stop you… it doesn't have to be me, but someone else will find a way to defeat yo-"

A spike formed from the living floor interrupted her, piercing her already drained aura and skewering her through the gut. Salem simply took a single stride forwards, and lifted Summer's face with her hand, "I'm sorry, what were you saying?"

Summer coughed up blood, and her body began going through shock from the quick yet severe injury, but she forced a single memory to the forefront of her mind as her eyes flashed with the intensity of a thousand stars.

At that exact moment, the screens in her machine displayed the countdown reaching zero. Taped beside her controls was a picture of Summer in a hospital bed, holding her newborn daughter, Ruby, in her arms as her stepdaughter, Yang, looked up at them in excitement.

All surrounding Grimm and landscapes were obliterated in the resulting explosion.

Author's Note:

Hello, and welcome to this... thing! I recently got into a bunch of Mecha series and am also still an fan of RWBY, so naturally I thought "What if I mixed them together?"

One idea I've had buzzing in my head is whether or not I should include mecha references besides the one I've shown that's clearly inspired by Getter Robo, and whether or not I should include characters from those franchises and make this a full on crossover instead of just an AU.

But anyway, until next time!