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The needle on the heart rate monitor flatlined at exactly 3:17 AM. Nobody noticed until the morning shift nurse walked in six hours later, her coffee slipping from her fingers when she saw the empty bed.
Izuku Midoriya's last thought had been about All Might's smile—that impossible, reassuring grin—before the darkness swallowed him whole. Then, for a while, there was nothing. No dreams, no awareness, just the absence of everything. Until there wasn't.
Pain came first. A dull, throbbing ache radiating from every joint, like his bones were being stretched apart. Then heat—unbearable, wet heat pressing against his skin. Something rough scraped against his palms as he tried to push himself up. His hands... didn't feel right. Too thick, too heavy.
He opened his eyes to a blur of green and brown, his vision swimming. The ground beneath him trembled slightly with each labored breath. It took three tries to focus, and when he did, Izuku saw claws. Enormous, curved claws digging into damp earth. His claws.
A shadow passed overhead. Not a cloud—something massive, leathery-winged. The sound it made wasn't human, wasn't anything he'd ever heard before. It rattled his ribs from the inside.
"Wh—" His own voice startled him. Too deep, too guttural. The word died in his throat as his tongue brushed against rows of serrated teeth. He tried again. "What...?"
Movement to his left. A snort, wet and animal. Slowly, Izuku turned his head.
Yellow eyes stared back.
The yellow-eyed creature tilted its massive head, nostrils flaring as it took in Izuku’s scent. Its body was a nightmarish fusion of scales and muscle, a predator built for tearing flesh—something between a raptor and a wolf, but larger. Izuku's instincts screamed at him to run, but his new body refused to move, still grappling with the sheer impossibility of his own existence.
"Y-You..." Izuku managed, his vocal cords straining against unfamiliar sounds. The creature blinked, then let out a low, rumbling growl that vibrated through the ground.
Before he could react, the beast lunged—not at him, but past him, jaws snapping shut on something small and furred that had been creeping through the underbrush. The crunch of bones was obscenely loud. Izuku's stomach twisted, but his new body responded differently—a pulse of hunger, primal and insistent.
A voice cut through the chaos, rough and guttural but unmistakably language. "First time?"
Izuku whipped his head around (too fast—his neck wasn’t built for this) and saw another figure emerge from the trees. This one walked upright, but its proportions were all wrong—too tall, too lean, with elongated limbs and claws that scraped against its thighs as it moved. Its face was more human than the yellow-eyed beast, but only just, the skin stretched tight over sharp cheekbones.
"First... time?" Izuku echoed, the words thick in his mouth.
The creature—no, person—chuckled, a sound like rocks grinding together. "You’ve got that look.
The words hung between them, thick with implication Izuku didn't understand, when his vision fractured abruptly. A grid of glowing blue lines spiderwebbed across his sight, resolving into a floating display that made his pupils contract painfully.
**SYSTEM REBOOT COMPLETE**
**USER: IZUKU MIDORIYA (QUIRK: EVOLUTIONARY SHIFT)**
**PRIMARY FORM: TYRANNOSAURUS REX (JURASSIC WORLD STRAIN)**
**SECONDARY FORM: HUMAN (BASE TEMPLATE)**
Izuku's breath came in short, hot bursts, each exhale stirring the ferns beneath his snout. The text shimmered like a heat mirage, unaffected when he snapped his jaws experimentally. The upright creature watched with something like amusement, its clawed fingers twitching.
"Interface finally kicked in, huh?" It—no, *he*—tilted his head, revealing a jagged scar running from forehead to jawline. "Took mine three days. Nearly got eaten by a pack of troodons before I figured out how to activate camouflage."
A translucent slider appeared at the edge of Izuku's vision labeled **FORM SHIFT PROGRESS: 0%**. Below it, pulsing gently: **CONCENTRATE TO INITIATE TRANSITION**.
The yellow-eyed beast finished its meal with a wet swallow and eyed Izuku with fresh interest. His claws dug deeper into the soil as adrenaline—or whatever passed for it in this body—flooded his system.
"Focus," the scarred man said, sharper now. "Unless you want to stay lunchmeat."
Izuku squeezed his eyes shut (too many eyelids, he realized distantly) and imagined his hands—human hands, freckled and scarred from years of training. The slider twitched. **5%**. A searing pain lanced down his spine as something inside him *clicked*.
When he opened his eyes again, the world had shifted subtly—colors duller, scents muted. His forelegs... no, his *arms* trembled violently, patches of green scales still visible beneath rapidly paling skin. The slider read **12%**.
The scarred man whistled. "Fast learner. Took me eight hours to get past the claws." He crouched—a movement that should've been impossible with those elongated limbs—and poked Izuku's partially transformed forearm. "Name's Gorou. Welcome to 2142, hero."
Izuku's vocal cords snapped back into something resembling human configuration with an audible *pop*. "All Might—" he gasped, the name triggering another surge. **34%**. His ribs shrank inward, forcing a cough that splattered dark blood onto the ferns.
Gorou's nostrils flared. "Dead. Six years now." He stood abruptly, scanning the tree line. "We should move. Your little light show's drawing attention."
A distant screech split the air—something large, and getting closer. The yellow-eyed beast bristled, emitting a subsonic growl that made Izuku's remaining scales vibrate.
**58%**. Izuku's tailbone retracted with a series of sickening cracks. He barely registered Gorou hauling him upright by one half-formed arm, his human legs buckling under unfamiliar weight distribution.
"Concentrate on your feet," Gorou hissed. "One toe at a time unless you want to outrun a carnotaur on stumps."
Another screech, closer now. Trees shuddered where something massive pushed through. Izuku's vision swam with overlapping warnings—**SYSTEM OVERLOAD**, **TRANSFORMATION STALLED AT 72%**—as Gorou dragged him backward. His left foot was still a three-toed monstrosity, scales splitting open to reveal raw pink flesh beneath.
The ankylosaur's armored tail swung inches from Izuku's snout, close enough for him to taste the iron tang of old blood crusted between its bony plates. He held perfectly still—not out of fear, but routine. Three years of pretending to be just another asset in Jurassic World's menagerie had taught him the art of calculated docility.
"Subject 09-M still shows abnormal hesitation during live feeding," Dr. Chen remarked into her tablet, the device's glow reflecting off her glasses. Behind the reinforced observation glass, she tapped a command that made the arena's sprinklers hiss to life. The scent of synthetic rain triggered Izuku's instincts—his muscles coiled automatically, but he forced himself to slump into the "submissive posture" the handlers rewarded. Let them think he was broken.
Gorou's voice echoed from memory: *They'll dissect you the second they realize you're more than code and teeth.*
The ankylosaur lumbered away as keepers in shockproof suits entered, dragging a still-twitching triceratops calf between them. One handler—Jenkins, his badge read—flinched when Izuku's golden eye tracked the movement. "Christ, this one's always watching," he muttered, triggering the remote feeder.
Izuku let his tongue loll as he crunched through the offered meal, suppressing the bile that rose when the calf's warm blood hit his palate. The real hunger—the human hunger—gnawed at him in quieter moments, when the night shift left him alone with the stars visible through his enclosure's dome.
At 0200 hours, when the biodome lights dimmed to simulate moonlight, Izuku pressed his spine against the false rock formation hiding his secret. His claws scraped a precise rhythm against the synthetic stone until a panel clicked open, revealing the stolen tablet he'd waterproofed with raptor hide. The screen flickered to life, displaying hacked security feeds and old hero forums.
A grainy video played on loop: All Might's final interview before the quirk singularity event. *"Even when the world changes,"* pixelated All Might grinned, *"what matters is—"* The feed cut to static.
Izuku's claws left hairline fractures in the tablet casing. Six years dead. Three years hiding. His reflection in the black screen showed a monster—eight tons of engineered predation with scars from "behavioral conditioning" crisscrossing his snout.
The alert came at 0247—a priority message buried in the park's intranet. Izuku's slit pupils dilated as he decoded it: *Containment breach in Sector 12. Asset 07-I (Indominus) unaccounted for.*
His crest spines stiffened. They'd revived *her*?
Screams erupted in the distance, muffled by concrete and jungle. The ground vibrated with something heavier than footsteps. Izuku hesitated—then exhaled through his nasal cavities in a decision made years ago.
With a convulsive shudder, his quirk activated. Bones hollowed. Scales inverted into skin. When the night guards came running past his enclosure minutes later, they found only an unconscious handler in a torn uniform—a freckled young man with bite marks mimicking raptor claws already fading from his arms.
"Medic!" Jenkins yelled, dragging Izuku's human form upright. "This kid's alive!"
Izuku coughed theatrically, pressing a palm to his bleeding forehead. His other hand slipped Jenkins' keycard. Beyond the trees, something roared with the voice of engineered annihilation.
All Might's words burned hotter than the transformation fever: *What matters is—*
—showing up.
**FORM SHIFT PROGRESS: 100%**
The Indominus's roar shook the facility’s foundations, rattling the IV bags in the medical bay where Izuku slumped against Jenkins' shoulder. But beneath the chaos, beneath the distant screams and automated lockdown alarms, something else tugged at him—not from outside, but *within*. A phantom limb he'd forgotten he had, twitching back to life after six years of silence.
One For All burned.
It wasn’t pain. It wasn’t even heat. It was *recognition*, the vestiges of a quirk that had outlived its host reaching across time and biology to reconnect. Izuku's human fingers spasmed against the medic’s shoulder as the power surged—not through his veins, but through something deeper. His DNA? His soul? The embers flared brighter with each ragged breath, syncing with the primal rhythm of his dinosaur heart still humming beneath layers of borrowed flesh.
"Kid? Stay with me—" Jenkins' voice warped as One For All *pulled*, not upward toward Izuku's consciousness, but *sideways*, into the quirk’s own memory. The world dissolved into a kaleidoscope of fractured moments:
*A warehouse roof. All Might’s skeleton hand outstretched. "You too can become a hero—"*
The vision shattered as Jenkins dragged him through a security checkpoint. Izuku's sneakers squeaked against sterile tiles, his human body still thrumming with the afterimage of power. His stolen keycard slipped between his fingers—not from clumsiness, but because his palm was glowing. Not the familiar crackle of One For All’s energy, but something *older*, greener, pulsing in time with the Indominus’s distant footsteps.
"Shit, is that a quirk manifestation?" Jenkins fumbled for his shock baton, eyes wide. "But the scans said you were—"
Izuku moved without thinking. His fist connected with Jenkins' jaw in a burst of emerald lightning—too precise, too controlled for a body that hadn’t fought in years. The guard crumpled, but the power didn’t stop. It coiled around Izuku’s bones like a second musculature, whispering in a voice that wasn’t his own:
*"You’re ours."*
The Indominus’s roar shook the facility again, closer now. Izuku stared at his trembling hands—human, freckled, *wrong*—as scales rippled across his knuckles against his will. His quirk interface flashed a corrupted error: **EVOLUTIONARY SHIFT OVERRIDE DETECTED**.
One For All wasn’t just *in* him anymore. It was rewriting him.
A security feed flickered on a nearby monitor, showing Sector 12’s mangled gates. Something moved in the static—not the Indominus’s hulking form, but a flicker of yellow lightning amidst the destruction. Izuku’s breath caught. That wasn’t possible. Unless—
The screen exploded in a shower of sparks as the Indominus’s tail whipped through the camera’s view. Izuku was already running toward the destruction, his stolen scrubs flapping around legs that lengthened unnaturally with each stride. His quirk interface stuttered: **75% REVERT PROGRESS—WARNING: GENETIC INSTABILITY**.
He didn’t care. Because beneath the Indominus’s bestial screeches, beneath the screams and the klaxons, he heard it—the unmistakable sound of a Detroit Smash.
All Might was dead.
But One For All wasn’t.
And it was fighting.
Izuku's vision tunneled into primal focus as his body reshaped itself with terrifying precision. Bones elongated, muscles thickened, and his skin split into armored scales that gleamed under the emergency lights. But the most overwhelming change was the heat pooling low in his abdomen—an instinctual drive that burned through any remaining human restraint. His quirk interface flickered frantically: **WARNING: REPRODUCTIVE INSTINCTS OVERRIDE ACTIVE**.
The Indominus across the ruined corridor wasn't just an enemy anymore. She was *potential*. Her scent—musky and rich with pheromones from the chase—hit Izuku's flaring nostrils like a physical punch. His answering growl vibrated through the shattered concrete as his body *moved* without conscious thought, massive tail swaying to counterbalance the sudden weight surging between his hind legs.
She paused mid-lunge, nostrils flaring as she registered the change. Her golden eyes dipped to the thick, tapered shaft now prominent against Izuku's underbelly, dripping with primal urgency. A sound escaped her—not a roar, but a low, considering rumble that made the glass remnants tremble.
Izuku's human mind screamed somewhere far away, but his dinosaur hindbrain was already advancing, claws scoring deep grooves in the tile as he circled her. The Indominus didn't retreat. Instead, she arched her spine invitingly, tail lifting just enough to expose the glistening slit beneath. The message was unmistakable.
When he mounted her, it wasn't gentle. The facility's remaining windows shattered under their combined roars as Izuku's hips pistoned forward, sheathing himself to the hilt in one brutal thrust. Her answering snarl held more challenge than pain, her claws raking the floor as she pushed back against him.
**QUIRK SYNCHRONIZATION 89%**, his interface blared through the haze.
Then—*fractures*. Memory shards tore through Izuku's consciousness: All Might's grin superimposed over the Indominus's snapping jaws, the scent of her musk blending with the ozone crackle of One For All. His thrusts grew erratic as the power surged between them, green lightning dancing along their conjoined scales.
She threw her head back with a scream that wasn't entirely animal as the energy crested—and Izuku *bit down* on her crest spines, holding her steady as their climax hit like a detonation. The walls cracked. The ceiling rained debris. And deep in Izuku's marrow, something *clicked* into place.
The Indominus collapsed beneath him, sides heaving. Izuku expected her to turn violent—expected claws and teeth—but she merely nudged his flank with her snout before limping toward the exit. A notification blinked in his vision: **EVOLUTIONARY SHIFT COMPLETE. NEW GENETIC MATERIAL INTEGRATED**.
Humanity crashed back in like a tidal wave. Izuku staggered, his monstrous form melting away into something bipedal and gasping. His hands—*human hands*—trembled as he touched his own face, sticky with fluids he didn't want to identify.
Then the wall exploded.
Gorou landed in a crouch amidst the dust, his elongated limbs now crackling with familiar yellow energy. His scarred face twisted in disbelief as he took in Izuku's naked, shuddering form.
"You *bred* her?" Gorou hissed. "Of all the—" A chunk of concrete sailed past his head as the Indominus roared from somewhere deeper in the facility. Gorou's glare could've melted steel. "Congrats, hero. You just made the smartest predator in history *hormonal*. Hope your quirk comes with child support."
Izuku vomited.
Gorou tossed him a stolen lab coat. "Get up. She'll be back for round two once she processes what you pumped into her." His eyes flickered with stolen embers of One For All. "And we've got worse problems."
The ceiling groaned ominously. Somewhere above them, something *bigger* than dinosaurs began to stir.
The lab coat clung to Izuku's damp skin as the facility trembled again—not from the Indominus this time, but from something deeper, like the earth itself recoiling. His fingers twitched, still tingling with the phantom sensation of scales. Gorou's stolen embers of One For All pulsed erratically in his own chest, out of sync, like a fractured echo searching for its source.
"You feel that?" Gorou snarled, claws digging into his temples. "It's *calling* you."
Izuku's knees hit the ground as the pull intensified. Not pain—*purpose*. His stolen tablet, still clutched in his shaking hands, displayed a security feed of Sector 12's ruins. Amidst the debris, the Indominus paced in agitated circles, her golden eyes flickering with the same green lightning that now crackled along Izuku's human veins.
One For All wasn't just in him. It was in *her*. And it wanted to merge.
Izuku's transformation didn't start slow this time. His bones *shattered*—not breaking, but *unfolding*, each fracture blooming into new configurations as his body remembered the Indominus's genetic imprint. Scales erupted across his skin with wet, tearing sounds, his spine elongating grotesquely as his jaw unhinged.
But the real change was deeper.
One For All *ignited* within his dinosaur heart, flooding his monstrous veins with emerald fire. The power didn't stop at his muscles—it permeated every cell, rewriting his biology in real time. His crest spines glowed like live wires, crackling with energy that scorched the air. His interface screamed: **OVERRIDE DETECTED: QUIRK SYNCHRONIZATION 100%**.
When he roared, the sound wasn't purely bestial. It thrummed with the resonant *boom* of All Might's voice, shaking the facility's foundations.
The Indominus answered immediately—not with aggression, but with startling synchronization. Her own crest spines flared with identical energy as she charged toward his location, her movements suddenly too precise, too *intentional*. She wasn't hunting anymore. She was *converging*.
Gorou barely yanked Izuku's tail out of the way before the Indominus barreled through the wall, her massive head swinging toward Izuku with eerie focus. Their gazes locked—golden eyes meeting gold—and the energy between them *cracked* like a live circuit finding completion.
One For All's vestiges howled in recognition.
Izuku understood then—really understood. The quirk hadn't just survived All Might's death. It had *fractured*, scattering its essence across the genetic waste of Jurassic World's experiments. The Indominus wasn't just carrying his offspring. She carried *him*. A piece of All Might's soul, wild and untamed, fused with dinosaur DNA.
And now it wanted to be whole again.
The Indominus lunged—not to attack, but to *connect*. Her jaws closed gently around Izuku's glowing crest, and the contact sent a surge of power so violent it blew out every light in the facility. In the darkness, their combined energy painted the ruins in pulsing green, their forms blurring at the edges as One For All wove them together at the molecular level.
Gorou's scream was distant, irrelevant. "You idiots are making a *nuclear reactor* out of—!"
The rest was lost in the detonation.
When the light faded, Izuku stood—no, *loomed*—in the ruins, but he wasn't just Izuku anymore. He wasn't just the Indominus either. His body thrummed with the perfect synthesis of both, his scales humming with stored energy, his mind alight with the clarity of *two* apex predators merged into something greater.
His interface flickered once before dissolving into a single, glowing command:
**EVOLVE**.
And so he did.
The Visitor Center’s shattered glass crunched under Sky’s talons as she dragged the last of the shredded park banners into their nest. The name had stuck—*Sky*—not because the Indominus could fly, but because of the way her eyes reflected the clouds when she hunted. Three and a half months of circling each other, of Izuku’s half-human hesitations and her impatient snarls, and now this: the scent of amniotic fluid thick in the air as her body prepared to expel their clutch.
Izuku’s transformed claws hesitated over the nest’s perimeter, his scales still flickering with residual green energy. He’d built this—not just the nest, but *them*. Every time Sky arched her spine in discomfort, his quirk reacted instinctively, One For All’s embers flaring to soothe her contractions. The power had changed since the fusion. Less lightning, more *pulse*, like a second heartbeat synced to hers.
"Breathe," Izuku rumbled—a useless suggestion, but the human part of him couldn’t stop trying. Sky responded by sinking her teeth into the mangled T.rex skeleton they’d repurposed as a nest frame, the bones groaning under her grip. Her golden eyes locked onto his, pupils blown wide with primal focus. The message was clear: *Stop hovering.*
The first egg came at dusk, slick with fluid that steamed where it hit the cool concrete. Sky’s roar shook dust from the collapsed ceiling as she nudged it toward the nest’s center with surprising delicacy. Izuku counted the ridges along its surface—eighteen, pulsing faintly green—before the second egg forced its way into the world. This one was darker, its shell threaded with veins that mimicked his own quirk scars.
By the third egg, Izuku’s instincts overrode his humanity entirely. He crouched behind Sky, his massive forelimbs bracing her trembling haunches as she pushed. Their synchronized growls resonated through the abandoned park, scattering the compies that had been lurking in the shadows. The egg plopped onto the nest’s padding of ferns and employee uniforms, its surface iridescent like oil on water.
Sky collapsed sideways, her flanks heaving. Izuku nuzzled her crest spines—*his* crest spines now too—and tasted metal. The eggs weren’t just eggs. They hummed with the same energy that had fused him and Sky together, their shells conducting One For All’s power like batteries. The fourth egg, smaller than the others, glowed intermittently, as if something inside was *testing* its strength.
Dawn painted the ruins in pale gold when the final egg emerged. Sky’s exhaustion was palpable, but she still managed a warning snap when Izuku reached to inspect it. This one was wrong. Not in shape or size, but in *texture*—its surface shifted like liquid, absorbing the light rather than reflecting it. Sky nudged it away from the others with her snout, her nostrils flaring at the scent. Izuku’s quirk recoiled instinctively, One For All’s embers dimming where the egg’s shadow touched him.
Gorou’s voice echoed from the broken escalator: "Oh good, you made nightmare fuel." He limped into view, his elongated limbs now permanently crackling with stolen energy. His scarred face twisted as he eyed the aberrant egg. "That one’s *his*, isn’t it? All Might’s leftover will playing with dinosaur DNA."
Izuku’s growl was automatic, but Sky surprised them both. With a tired huff, she rolled the dark egg back toward the nest’s center, her tail thumping possessively around the entire clutch. The message was unmistakable: *Ours.*
Outside, the jungle fell silent. Not the quiet of absence, but the stillness of predators holding their breath. Something watched from the trees—something with eyes that glowed the same toxic green as Izuku’s quirk. Sky bared her teeth at the shadows, but her exhaustion made the threat hollow. Izuku positioned himself between their nest and the unseen observer, his scales flickering in challenge.
The eggs pulsed in unison, casting jagged shadows across the Visitor Center’s ruined mosaics of dinosaurs. One shadow, darker and sharper than the rest, stretched toward them—not from the jungle, but from the aberrant egg itself.