AN: Well, after 2 years, I've finally gotten to writing this AU. As a preface: Zero does not have amnesia. It should be obvious in the text, but making it clear. Additionally, X and Zero are in an established romantic relationship by the start of the story.

Want to thank my friend Vox buglesbian on twitter for being my beta reader and editor!
I will try my best to upload chapters in a timely manner, but work and uni and all that. Either way, hope you all enjoy DAVAOR

PROLOGUE

Miles beneath the hallowed city of Neo Arcadia, a lone reploid ran for his life through a forgotten labyrinth of tunnels, horrified to realize that he was the last man standing between the tyrant king X and the Resistance's last hope.

Zero's fate following the end of the Elf Wars was a myth, at best. Long decades had passed following the war's final battle against Omega, the legendary reploid disappearing shortly after Omega and Dr. Weil were exiled from Earth. After years of silence, many had assumed the worst and mourned the loss of their beloved hero, though an adamant few refused to give up hope that Zero was still out there somewhere. Indeed, the esteemed Resistance commander Ciel had given up countless nights of sleep over the years digging up lost archives, decrypting data logs written in obscure code and mapping Neo Arcadia's ancient subterranean infrastructure to piece together the truth of what happened to Zero all those years ago.

Somewhere, deep beneath the surface, Zero lay dormant. The former maverick hunter, now a saviour of humanity, had remained hidden in stasis for decades, waiting for someone worthy- or maybe just desperate enough- to wake him. In secret, he had sealed himself away in a laboratory, where he had been forgotten by the people he vowed to protect as the world he fought so hard to build crumbled around him.

The Resistance couldn't fight X's rule alone anymore. They were no closer to freedom than they had been decades ago, when the struggle for justice began. They couldn't wait any longer. They needed Zero.

Unfortunately, so did X.

And so the lone reploid Colbor, the last soldier left alive after X had intercepted his squad in the underground ruins, was saddled with the task of finding Zero before the mad king could. Colbor could do nothing but run, guided by the voice of Ciel over his comms unit, until he found the long-forgotten laboratory where Zero was sealed. Trailing close behind was X, flanked by his sons, the generals Sage Harpuia and Hidden Phantom. The loud thudding of footsteps and the king's orders echoed through the never ending maze of corridors.

The halls of the underground research facility were decrepit, waterlogged, their walls rotting away and collapsing inwards after nearly a century of neglect. Even with Ciel's navigation in his audial, Colbor was struggling on his own. It was dark, and in his bid to outrun X, he had been running in circles, to the point where he didn't quite know where he was. The reploid stumbled through the flooded passageways, vision blurred and thoughts racing as his overclocked systems ran too fast and too hot in a sheer panic.

Colbor pivoted, almost falling in a hard turn right into another long corridor. He looked over his shoulder, paranoia gripping his soul with its bitter cold talons as X's voice became ever louder, the tyrant closing in on him quickly despite his best efforts. He held his finger firmly on the trigger of his blaster, knowing damn well he wouldn't do so much as scratch X's armour. Colbor was haunted by the memory of the menacingly adept reploid making quick work of the rest of his squad, their shots merely bouncing off of the mad king as he tore through them in a frenzy. He swallowed hard. He was getting tired, and X was getting closer now…

"Just 500 more metres and a left turn, Colbor."

Ciel's voice came as merciful relief for the Resistance soldier. Colbor could barely respond, the words thick in his throat as terror seized his frame.

"C-commander, X is hot on my trails. D-don't know if I'll make it." Despair had quickly begun to sink in, its hold on him tightening with every second that passed by. He couldn't get air into his systems fast enough to cool them, the beat of his fuel pump pounding in his head as he struggled to focus. His internal radar displayed the rapidly shrinking distance between him and X, alongside the myriad of overheating warnings crowding his HUD.

"Just try. The code to the laboratory should be 145290."

Despite his panic, Ciel was counting on him… Zero, the Resistance, the future of Neo Arcadia, they were all counting on him. He couldn't stop. He had already come this far. "Copy that. I-I'll do what I can."

"That's all I ask. Good luck, Colbor."

With that, he made a right turn, just as Ciel had told him to. The reploid suddenly found himself face-to-face with a massive, ancient door, easily dwarfed by its impressive height. Compared to the rest of the underground facility, it was remarkably pristine— its silver metal frame was unscathed, a rainbow glow of data streaking through indents etched into its expanse, reminiscent of water flowing down a river delta. Behind those grand doors, Zero slumbered, waiting… ready to be reborn into a world that needed him more than ever before.

Colbor activated the console, resting his fingers on the numpad as the ancient locking device flickered to life, its interface monitor faded and dim. X was getting closer. All he had to do was input the code…

1... 4…

As he punched in the numbers with trembling hands, an ethereal voice spoke to him, its words weaving through the wind and cutting straight through him.

Stay out of this.

Colbor jolted upright, his blaster held at the ready, but when he scanned the area, he found that he was alone. All at once, the air turned cold around him, silence befalling the lone reploid, as if X and his sons were never there, trailing him…

Getting closer. Too close.

"You!"

A buster shot ripped through Colbor's leg, sending the reploid to the ground in an instant. The Resistance soldier cried out, a burning agony racing up from the bullet wound in his ankle to the rest of his leg like a climbing vine. His HUD flashed with critical injury warnings as he lost any mobility he had in that leg.

All Colbor could do was scramble onto his back, his gaze meeting the cold, crimson glare of the Neo Arcadian king himself... Master X.

The father of all reploids stood tall over Colbor, his strong brow furrowed in a furious scowl. Colbor was frozen as fear overcame him, his body refusing to obey his commands to fight back, or even just run. It was over… X would finally be reunited with his Zero. What was there to do now?

He prayed that Zero would do the right thing, even if it meant turning against X.

"I suppose I should thank you for leading me so kindly to my dear Zero," X sneered, kneeling down before Colbor. He wrung his hand around the reploid's feeble neck, lifting him and pinning him against the laboratory door. Colbor choked and sputtered as the hand around his throat tightened, X's grip effortlessly powerful.

The king's harsh red gaze narrowed as Colbor desperately tried to grab and claw at his wrist, fruitlessly attempting to pry himself free from X's punishing grasp. "But you should know better than to take what is rightfully mine."

Brimming with anger, X threw Colbor aside, the thin reploid landing at his sons' feet with a pained grunt, the blaster flying from his hand and clattering as it skidded across the ground. Just as the Resistance soldier regained his bearings, straining to reach for it, X fired another blast from his arm cannon, catching Colbor straight in the wrist. Another shot cut through his ankle, swiftly immobilizing the reploid with unmatched precision.

"Now get out of my way," X spat, kicking Colbor's limp body aside. Colbor, paralyzed from searing pain, the mechanical tendons in his limbs torn to ribbons, could only watch as X turned towards the door to the forgotten laboratory, brushing his fingers over its grand frame. The injured soldier's vision continued to blur as he leaked more and more fuel from a ruptured line, struggling to maintain consciousness as X's words swam around him. "I've waited for this for so long… Zero…"

Harpuia cleared his throat. X nodded with an acknowledging hum, but didn't turn to address him. "Father," he began, "do you want me to dispose of him?"

The air general dipped his helm downwards to Colbor, the Resistance soldier still writhing at his feet. Harpuia pinned him under his foot, talons digging into his chest, a weak sob ripped from the reploid as more fuel gushed from his injuries. X waved him off. "Don't bother. He won't make it long on his own like this. Besides, scavengers will find a good use for his parts," X answered. "I have far more important matters to attend to."

Phantom eyed the locking console, carefully setting his hand on the numpad. "The door is still locked," the shinobi noted. "We'll require the passcode, sir."

"No need, Phantom," X assured, placing a hand on his son's shoulder and pushing him aside. "Stand back."

Harpuia and Phantom dutifully obliged, inching back. X raised his buster and charged a shot, piercing the massive door with a single powerful blast, exposing the decaying underground laboratory once the dust had settled.

Retracting the cannon back into his arm, X grabbed either side of the opening that split the door in half, gritting his teeth as he pried open an entryway with little more than his formidable brute strength. He had waited for far too long… it was time he was reunited with his partner, lost to time.

The laboratory within had long since been reclaimed by nature. Vines descended from the ceiling, while invading roots formed cracks in the walls, creating an opening for the trickles of groundwater that had slowly flooded the room. X and his children climbed through the hole seared through the door, footfalls accompanied by loud plunks as they stepped into the ankle-deep water stagnating on the floor of the room. Sensing their presence, battered fluorescent lights flickered on for the first time in an eon, bathing the old lab in faint, yellowed light.

And slumbering in the center of the deteriorating lab, cradled in a tangle of wires and cables, was Zero. The legendary reploid, awash in the warm glow of faded lights, lay dormant before X, bound to countless machines still dutifully keeping him locked in a coma and recording his feeble vital signs. X extended a hand to his side and motioned Harpuia and Phantom to stay back as he inched closer to Zero, gingerly reaching out to his partner, who he had once feared he had lost forever to war.

Now that X was footsteps away, he could see his beloved clearly. Even when he was weak and thin— worse for wear from his years in stasis— Zero was still as beautiful as he recalled. Under a coat of dust, his armour still shone a stunning red, his face so fierce and yet so soft and elegant… and that gorgeous blonde hair a mess, golden locks cascading down from his helm like fine amber silk.

X was overcome with awe. Frozen and speechless, just like the moment he had first met him centuries ago when he was a mere B-rank Hunter. He reached out to cup Zero's cheek, brushing his thumb down his face and pushing a stray lock of his hair aside. He looked so serene and pretty like this, at peace in his slumber, where the turmoils of reality couldn't trouble him anymore. X brought him closer, pressing Zero's headgem against his and grabbing a hold of his arms, his frame so comfortably warm compared to the cool air around them.

"Zero… It's really you…" X murmured, shutting his eyes and taking in his former partner's presence. Zero imparted an unmatched sense of fulfillment and wholeness that he hadn't felt for decades. He had dreamed of the day he'd finally reunite with his beloved Zero— even after years of ruling Neo Arcadia alone, X had never let go of that desperate hope.

And now… with Zero at his side, the paradise of Neo Arcadia would finally have both of their saviours to rule over them, to guide the good people of his kingdom into a new era of peace and prosperity. It was everything that X had always wanted.

X stepped back, slipping his touch down Zero's lithe arms to his hands, weaving his fingers through Zero's own. Such delicate, beautiful hands, capable of such unknowable destruction…

Bittersweet memories of their past washed over X in an instant. Memories of losing him again and again, of the Eurasia incident, of the devastation of the Elf Wars… oh, how he loved Zero, even if it would be the death of him. Zero's love was like no other, irreplaceable in the way it made X truly feel alive.

One way or another, Zero was made for him.

"Phantom," X called upon his son, the shadow general standing at attention in an instant. "Bring him out of stasis."

X didn't move from where he stood before Zero, his hands held tightly in his grip and gaze fixed upon his old partner's face. "Very well, Master X," Phantom replied with a small bow of his helm, making his way over to the laboratory's main console and brushing a thick layer of dust from its user interface. Phantom made quick work of rebooting the aged computer machinery from its own long slumber, the system humming to life with a resounding whirr of battered cooling fans.

The post-war code that the programs were written in had been retired decades ago, and the last data log that had been recorded was dated to 2216– before Phantom had even been activated. Though his curiosity was piqued, there was no time for the shinobi to analyse such ancient tech. Master X had waited long enough to be reunited with his Zero.

As Phantom executed the revival protocol, he felt a cold wind cut through him. Someone, somewhere, was watching them, and they were making it abundantly clear that they were not welcome here.

There was no going back. Harpuia and Phantom watched the computer terminal process a cascade of commands, wondering if what they were doing was right.

X took a step back, watching with rapt attention as Zero slowly woke from his century long slumber. The tangle of cables and wires detached themselves from Zero's frame with a sharp hiss, the red android snapping his eyes open with a gasp.

In a state of delirium, his body weak from years of stasis, Zero's legs buckled. He collapsed from his nest of wires, X dashing forward to catch him in his arms. Harpuia and Phantom rushed to their father's side. X had always told them of the legendary reploid Zero, and there was no shortage of artistic tributes to the heroic swordsman amongst Neo Arcadia, but to see him in the flesh, dazed and thin in X's arms…

To the brothers, Zero looked far more vulnerable than the image X painted in their minds of the hardened warrior he fell for.

"Zero…" X murmured, his voice wavering with the flood of emotion surging through him. He cupped Zero's face and reached an arm around his waist, holding him tight to his chest as if he was going to lose him again. Even the way Zero's striking eyes gazed up at him, indigo in the shadows and ice-blue in the light, filled X's soul with the warmth it had lost years ago, when he had lost his way without Zero at his side.

He'd missed the way Zero fit so perfectly in his embrace.

The world was still spinning for Zero, senses adjusting to being active again after… he didn't even know how long it had been since he sealed himself away. Everything was a blur, from the room he was in to the voices he was hearing to the reploid who was currently holding him in a very familiar embrace.

"Where…" Zero began, his vocalizer still quiet and fried as he slowly worked it back to its fullest function. "Where am I?"

"It's okay. You're safe, Zero," X replied softly. "You're with me now."

Zero narrowed his gaze, reaching a hand upwards to caress X's face with a featherlight touch. "X… is that you?"

His voice was still faint and husky, but it was all that X wanted to hear. It had been years since he'd heard that sweet, gently deep voice, and his words hung in the air long after they had been spoken. X could feel a lump forming in his throat. "Zero, i-it's me," he whispered, voice hitching, "It's me, X."

When Zero's broken vision finally focused, the red reploid closed his eyes and let out a breathy laugh as the realisation of his circumstances set in. "...Took you long enough."

X managed a soft chuckle, words escaping him. What was there to say? There was so much Zero needed to know. He had missed out on a lifetime of memories.

Zero groaned and stirred in X's arms. "H-how long… have I been asleep?" Zero asked, scanning the ruins of the lab with a half-lidded gaze. "X— agh, I feel terrible..."

X hushed him, pulling him closer to his chest. "You must be suffering hibernation sickness. Just rest, Zero. I'll bring you home," he promised softly. "I'll tell you everything when we get there."

On the brink of passing out once more, Zero mustered up a small, but nonetheless beautiful smile. "Thanks, X…" Zero murmured, his voice no more than a whisper as his systems began to shut down again, energy reserves critically low. "I love you."

Hearing those words from Zero was the one thing X had missed the most. "I love you too, Zero," he answered in kind, just as Zero slipped back into unconsciousness, his head falling back and eyes fluttering shut.

X could've stayed in that moment forever— Zero in his arms, finally reunited with his other half. With Zero at his side again, X felt invincible. Neo Arcadia's legendary red reploid has returned, brought back safely in the arms of the brutal reploid father. As he admired the slumbering Zero, X swore to himself he would never let Zero slip from his grasp, even if it meant burning down the world he had created.

"Father." Harpuia stepped forward, snapping X out of his thoughts. "We should get going. Fefnir just alerted me that he's detected Resistance reinforcements entering the east cistern entrance heading in our direction."

"Then they're wasting their time. I have what I've been looking for," X assured, hoisting Zero's limp, light body into his arms. "Tell your forces to withdraw from this sector. I'll see you two back at the citadel."

Before Harpuia could say anything else, X was gone in a flash of blue light, taking Zero with him.

The brothers, left alone, exchanged looks. Harpuia vented his nerves with a sharp sigh.

"This is General Harpuia. All units, withdraw from the area immediately." The air general spoke into his comms unit once the silence had become too much to bear. "Master Zero is in our possession."

Cutting off the link to his comms system, Harpuia turned to Phantom. "...I'll see you there."

Harpuia departed through the Neo Arcadian transerver. Phantom, through the noise of computers humming and the trickle of groundwater, could hear the distant sounds of Resistance soldiers.

Even now, with the ancient reploid gone from the derelict lab, Phantom couldn't shake the foreboding sensation that something was watching him. The cold, thin air sent a chill through his tall frame.

...But Master X knew what was best, both for himself and for the people of Neo Arcadia. Perhaps Phantom was just being paranoid.

With Resistance reinforcements closing in on him, Phantom joined his brother, warping away just as Faucon's unit reached Colbor's unconscious body.