King Xarion from Ben 10: Ultimate Alien is an aging monarch obsessed with power and immortality. As the ruler of the declining kingdom of Zarkovia, he believes strength and authority are his birthright simply because he is king. Arrogant and condescending, he looks down on others—especially heroes like Ben Tennyson—as tools to be used. Beneath his royal pride lies a deep resentment of his own aging body. Frail, slow, and nearing the end of his life, Xarion despises his weakness and fears death. Desperate as his kingdom declines and his health fails, he becomes manipulative and willing to betray anyone if it means gaining the power and strength he believes he deserves. After discovering an ancient machine capable of channeling immense bio-electric energy, Xarion lures Ben into helping him recover the body of Dr. Viktor, secretly planning to use the machine to transfer his mind into Viktor’s powerful monster-like body. Using a device to control Ben’s transformation, Xarion forces him into the alien AmpFibian and connects him to the machine, draining the alien’s bio-electric energy to activate the ancient technology. However, the plan goes terribly wrong. Instead of transferring Xarion’s consciousness into Dr. Viktor’s body, the machine overloads. A burst of energy erupts through the chamber, and Viktor’s body disintegrates into nothing but ashes. Xarion stares in horror. “No… no…!” he whispers, panic flooding his voice. Realizing his one chance at power may be lost, the old king flees the chamber in desperation, rushing through the castle halls toward his private chambers. In his panic he doesn’t even notice something strange—despite his age, he runs swiftly and steadily, without stumbling or gasping for breath. He bursts into his room and slams the heavy door shut behind him. “No! No, no, no!” he shouts, striking the stone wall in rage. But the wall cracks. A deep dent forms where his fist struck. Xarion freezes, staring at his hand in shock. Slowly he begins to feel something changing. His body feels different—stronger. His muscles begin to grow beneath his clothes, swelling and becoming denser. His posture straightens as years seem to fall away from him. Strength floods his limbs, and his breathing steadies with newfound vitality. His skin gradually shifts to a pale grey tone. His white hair darkens strand by strand. His frame grows taller and broader, his muscles becoming powerful and imposing.

Chapter 1: The King’s Unholy Rebirth

The air in the transfer chamber still crackled with the scent of ozone and burnt flesh. King Xarion stared, his old, rheumy eyes wide with disbelief, at the empty space where Dr. Viktor’s body had been. Only a faint grey smear of ash remained on the metal dais, already settling into the grooves.

“No… no…!” The whisper scraped raw from his throat. Panic, cold and sharp, flooded his veins. It had failed. His one chance at true power, at usurping Viktor’s brilliant mind and robust form, had evaporated in a flash of wild energy. Ben Tennyson, connected to the alien ampfibian, was still unconscious, the machine’s conduits sputtering weakly. All for nothing.

A raw, animal scream of fury built in his chest. He turned, his royal robes swirling, and fled.

He burst from the chamber, his heart hammering a frantic, painful rhythm against his brittle ribs. He expected the familiar ache in his joints, the shortness of breath, the stumbles. But they didn’t come. His legs pumped, carrying him down the torch-lit stone corridors with a speed he hadn’t known in decades. The portraits of his ancestors blurred past, their painted eyes seeming to widen in surprise. He didn’t notice. His mind was a cyclone of rage and terror.

He slammed the heavy oak door of his private bedchamber shut, the boom echoing in the cavernous space. Crimson velvet drapes hung still in the stale air, the room smelling of aged perfume and dust. The opulence felt like a mockery.

“No! No, no, no!” he roared, his voice cracking. He spun, and in a blind fury, drove his fist into the cold stone wall beside the door.

A sound like splitting rock echoed through the room. Not the crunch of breaking bone, but the deep, thunderous crack of solid masonry. Xarion froze, his knuckles were not even stinging. He pulled his hand back, trembling.

A deep, web-like dent was impressed into the wall. Stone dust trickled down.

He stared at his hand. It was his hand, yet… not. The liver spots were gone. The skin was taut over the knuckles, the veins prominent but strong. He turned it over, watching the play of muscle and tendon under the skin. A strange, humming warmth was spreading up his arm, throughout his body.

A strange, humming warmth was spreading up his arm, throughout his body. It wasn’t painful. It was… profound. A deep, cellular buzz, like a million insects waking up under his skin.

He could feel his muscles growing, slowly but surely, as he looked at his arms slowly growing. He didn’t even notice his king robe slipping from him and falling silently to the ground as he was mesmerized by his growing arms now straining the sleeves of his shirt. The fine linen, once loose, pulled taut across his biceps and forearms. His chest began expanding, the buttons of his shirt now groaning in protest as gaps in between buttons started appearing, revealing a glimpse of his now slightly grey, muscular pecs.

He stumbled backward, his balance off, his center of gravity shifting. His legs carried him to the full-length, gilded mirror near his colossal bed.

The reflection staring back was not his own.

His skin had become a pale, smooth grey, like polished stone. His white beard was slowly falling off, drifting down in wisps to litter the floor, revealing a defined jawline with fewer wrinkles than he remembered. His hair was becoming darker strand by strand, the silver receding from his temples as if being painted over with a brush of deep slate.

He looked at himself, and noticed his pants were getting tight around his thighs and ass as his muscles kept growing. He seemed to be getting slightly taller, because the sleeves of his pants and shirt were sliding up slowly, revealing his now defined calves and forearms.

And he started noticing a growing bulge.

It wasn't a gentle swell. It was an insistent, thickening pressure against the fly of his trousers. The fabric strained, the central button bowing outward, threads screaming. A hot, heavy weight was filling out, lengthening, until it pressed a blatant, urgent outline against the fine wool.

He was getting engrossed, and horny, as he could feel Dr. Viktor's power coursing through his veins. It wasn't just strength. It was a corrosive, arrogant vitality. It was hunger. It was a need to dominate, to claim, to use. The sheer, fuck-you potency of it coiled in his gut and pooled, burning, in his groin.

“Fuck,” he breathed, the word a rasp of pure wonder.

The ache in his groin was now a persistent, throbbing demand. He smirked at his reflection, savoring the obscene silhouette he cast. The fine clothes, symbols of his old, frail station, were now prisoners to this new form. He enjoyed the strain of the fabric, the way it hugged the unfamiliar power in his thighs and ass.

He started smirking as he flexed one bicep. The seam of the shirt ripped at the armpit with a sharp tear, revealing a patch of thick, black hair. A wave of his own scent—musky, alien, potent—wafted up. It made him even hornier. He repeated the motion with the other arm. Another rip, another flash of dark, hairy pit. He flexed both biceps together, the seams giving way completely, framing his powerful arms. His new-found alien musk enveloped him.

He became oblivious to his body still slowly growing. The shirt buttons started creaking loudly against his broadening, deepening chest. The zipper on his trousers slid down halfway on its own with a metallic whisper.

Pop.

The top button of his shirt flew off, pinging against the mirror. The placket parted, revealing a V of solid, grey pectoral. Xarion looked surprised for a second, then grinned hungrily.

“One down,” he murmured, his voice deeper, “five to go.”

He looked at himself in the mirror with a smirk. He pushed his pecs forward and rolled his shoulders back with a knowing grunt.

Pop. Pop. Pop.

Three more buttons burst in quick succession, flying across the room. The shirt gaped open, revealing his barrel chest, dusted with the same dark hair. He noticed then, from his nipples—they’d started leaking. A clear, slick bead of moisture formed at each tip. He could see the slight, damp stains already blossoming on the fine linen where his nipples had been pressed.

A low growl rumbled in his chest. He took the shirt by the front placket, his new grip iron-strong, and ripped. The final two buttons burst, followed by a sigh of relief.

He threw the ripped shirt to the ground and stared at his shirtless body in the mirror, at his slightly damp, pebbled nipples.

A power-deep shudder wracked his frame. He flexed his biceps again, this time holding the pose, watching the slabs of muscle in his arms knot and swell. His sweaty, hairy armpits were in full display, the dark thicket matted with a musk that was quickly engrossing the room. It was pungent, animal, tinged with something alien—ozone and spice. He inhaled deeply, nostrils flaring, and shoved his nose closer to one damp, hairy pit. The scent was overwhelming, primal. It was him. It was Viktor. It was power.

He inhaled greedily, absent-mindedly fondling one firm pec with his other hand, his thumb brushing over the stiff nipple. He was oblivious to the couple of droplets leaking from the tip, a clear, milky bead that rolled down the hard curve.

He switched, turning his head to bury his face into the other hairy armpit, shoving his nose deep into the damp heat as he caressed his other pec. Another few droplets escaped that nipple, tracing a path down his grey, sculpted chest.

Pop.

The sound was small, metallic, a pellet hitting the far wall.

Xarion flinched, pulled from his reverie. “Hmm?” He looked down.

His pants button was gone. The waistband hung open, the fabric now held together only by the strained zipper. Without the button, the zipper was struggling, the metal teeth parting under the relentless pressure from beneath. The king knew the trousers were next. The fabric was taut, the outline beneath it undeniable—a heavy, thick curve trapped against his hip, the fine wool darkening with a damp spot of pre-cum.

A laugh bubbled up from his new, deep chest. It wasn’t a sound of mirth, but of triumph. Of raw possession.

“Oh, finally,” he growled.

With a snarl that was more Viktor than Xarion, he hooked his thumbs into the waistband of his trousers and shoved them down, along with his undershorts. They caught on the fierce erection now springing free, and he tore at the fabric until it gave way.

His cock sprang free, thick and impossibly long, a veined pillar of grey flesh crowned by a deep, flushed head. A single, viscous pearl of pre-cum welled from the slit. His balls, heavy and full, tightened against the base.

“Viktor’s gifts,” he chuckled, the sound dark and grating. He wrapped his fist around his new cock. The heat was immense, the skin like heated stone. A jolt of raw pleasure, far more intense than anything his old body had ever mustered, shot up his spine.

The sensation was electric. His own touch was frantic, possessive. He pumped his fist, a brutal, quickening rhythm. The glide was smooth, the skin like hot silk over steel. He watched himself in the mirror, this powerful, grey-skinned stranger with his dark hair and youthful face, desperately jerking his monstrous dick.

Memories that weren’t his own flickered at the edges of his mind—Viktor’s memories. The cold satisfaction of a perfect calculation. The sharper, darker thrill of pinning a dissenter to a wall with a force-beam. The feel of a captive’s throat under his hand. Each fragment of stolen arrogance fed the fire in his balls.

His balls. They ached, drawn up tight, heavy sacks churning with a need for release. He cupped them with his free hand, groaning at the sensitive weight. He was going to come. He was going to unleash this stolen power in a raw, violent burst.

The pleasure built, a wave of crushing pressure. It wasn’t sweet. It was conquering. It was victory. It was the feeling of taking what you wanted and watching the light die in the eyes of whoever had it before.

“Yes… fuck… YES!” he roared, his voice deeper, resonant, shaking the dust from the velvet drapes.

He thrust his hips forward, fucking into his own furious grip. The climax tore through him like a detonation. Thick, voluminous ropes of cum shot from him, not white but a strange, opalescent grey. They splattered across the ornate carvings of the footboard with the force of a projectile, sizzling faintly where they landed. The first jet was so powerful it cracked the ancient, polished wood, a jagged split appearing in the rosewood.

He kept pumping, milking himself through the shuddering aftershocks, each pulse a lesser quake. He finally slumped, bracing himself against the bedpost, breathing in ragged, satisfied gasps. The smell of sex, ozone, and stone dust filled the air.

In the mirror, the pale grey god watched him, a smirk playing on its borrowed lips. The power thrummed, settled, became his. Not just the muscles, not just the youth.

Xarion looked at his reflection, at the spent, magnificent cock still in his hand.

He knew, with a cold, certain clarity, what this meant. The transfer hadn’t failed. It had simply… changed him. He hadn’t gotten Viktor’s mind. He had gotten his body’s blueprint, his physical essence, and the chaotic, hungry energy that powered it.

A slow, genuine smile spread across his new face. He didn’t need Viktor’s mind. Not when he had this.

He released himself, turning from the mirror. His gaze fell on a heavy, bronze vase by the window. He focused, not with his old mind, but with a new, instinctual part of his will. A crackle of green energy, Viktor’s signature green energy, snapped from his fingertip. The vase didn’t just shatter. It vaporized into a fine, smoking powder.

Xarion laughed, the sound rich and dangerous in the silent room. The game had just changed. Dr. Viktor was gone. Long live King Viktor.