[Blackgate Penitentiary, Gotham City — Evening]
Jack didn't bother hiding his stare.
The woman's features sharpened under the cell's fluorescent buzz—angular cheekbones, a mouth that defaulted to something between pout and sneer, brown hair let loose. Even stripped of makeup and crammed into an ill-fitted orange jumpsuit, she carried herself like she was posing for a magazine cover instead of standing in a concrete box that smelled of industrial bleach and decades of desperation.
Selina Kyle.
If he was right—and he was increasingly certain he was—then he'd transmigrated from one universe straight into another. Marvel to DC. A lateral move across the multiverse, the kind of crossover premise that powered a thousand fanfictions.
Jack smiled.
The smile lasted approximately half a second before her leg blurred toward his face.
Fast.
The strike came up from the hip with professional fluidity, heel aimed at his jaw with enough torque to shatter bone. Prison jumpsuit or not, this woman moved like she'd been breaking faces since puberty. Jack had exactly enough time for one coherent thought:
Infinite Copy.
Something clicked in his skull—not painful, just present, like a gear engaging. Information flooded his nervous system: weight distribution, hip rotation, the precise angle required to maximize kinetic transfer through the ankle. He didn't learn it so much as become it.
Jack dropped backward.
Her foot sliced the air above his face close enough that he felt the displaced breeze. His spine bent at an angle he couldn't have managed ten seconds ago, his center of gravity shifting with instinctive precision that felt borrowed—because it was.
The counter came without conscious decision.
His leg swept for her planted foot, targeting the precise gap between calf and knee where leverage collapsed. The strike connected. Selina's balance evaporated. Her body tilted toward him, and she was already correcting, her free leg retracting to catch herself on the mattress—
Jack caught her ankle.
He pulled.
She dropped into a full split, thighs pressing against the thin mattress with her weight pinning Jack beneath her. For one frozen instant, they were close enough that he could count her eyelashes.
Rrrrrip.
The sound echoed through the cell like a punchline.
Orange fabric parted along the seam. The prison-issue jumpsuit, evidently not designed with gymnastics in mind, had surrendered at the crotch.
Silence.
Selina stared down at him. Jack stared up at her. The fluorescent light hummed its tuneless song.
"Don't look at me," Jack said, breaking first. "I'm not paying for that."
Her expression flickered through several distinct phases—embarrassment, confusion, something that might have been reluctant amusement—before settling on pure, concentrated fury. "Did I ask you to pay?"
Her fist came down at his face. Given their positions, the trajectory made her target obvious. Jack rather enjoyed his ability to taste food, so he shoved her ankle sideways with enough force to topple an ordinary person.
Selina wasn't ordinary.
She converted the push into a backflip, landing in a crouch at the far end of the cell. The torn jumpsuit gaped. She didn't seem to notice or care. Her eyes stayed locked on Jack as he rose to his feet, and there was something evaluating in her gaze now—the look of a professional recalculating threat assessment.
"Cute trick," she said. "Where'd you learn to move like that?"
"Just now, actually." Jack rolled his shoulders. The copied combat instincts hummed beneath his skin, eager. "You're a good teacher."
Selina's eyes narrowed.
Then she came at him like a whip uncoiling.
The combination was textbook Muay Thai layered with something dirtier—street-fighting pragmatism that turned every surface into a weapon. Elbow at his temple, knee at his ribs, a eye-gouge feinted into a throat strike. Fast. Fluid. Vicious.
Jack matched her blow for blow.
Not blocked. Matched. His elbow met hers at the same angle. His knee rose at the same moment. When she feinted for his eyes, his hand mirrored her movement exactly. Their forearms cracked together in the narrow space, bodies twisting through identical geometries.
Selina's rhythm stuttered.
She threw a hook. He threw the same hook. She pivoted into a spinning back-kick. He pivoted into a spinning back-kick. Their heels nearly collided midair. The cell rang with the percussion of impact—fist against fist, knee against knee, the grunts and shuffles of two bodies executing the same choreography in a space barely large enough for one.
"What the hell," Selina breathed, dancing back. "What are you?"
Jack grinned. "Call it a learning disability. I pick things up too fast."
"Bullshit." She came at him again, faster now, frustration bleeding into her technique. Three-punch combination, low kick, elbow—and Jack intercepted each one with the exact motion required, no more, no less. It was like fighting a mirror. A mirror that kept smiling.
"Stop copying me!"
"Can't help it." Jack caught her wrist mid-strike, twisted, released. "You're just that inspiring."
Selina ripped her arm free. Sweat gleamed at her hairline, and her breathing had roughened. She was good—genuinely good, the kind of skilled that came from years of rooftop chases and back-alley brawls—but the harder she pushed, the more precisely Jack reflected her back at herself.
Infinite Copy. Even the micro-habits transferred: the way she loaded weight onto her back foot before a kick, the slight tell in her shoulder before a jab. He knew her fighting style as intimately as she did, minus the years of effort.
And that was only half of it.
"Fair warning," Jack said. "I've been playing nice."
Selina scoffed. "Playing nice?"
"You know." He settled into a stance that was hers and not-hers simultaneously. "Teasing the cat."
Something flickered in her expression—recognition, maybe, or the first stirring of genuine alarm. But Selina Kyle had never been the type to back down from a fight, not even fights she knew she couldn't win. She launched herself at him, leg swinging in a vicious arc.
Jack stepped inside the kick.
Infinite Superposition—One-fold.
The world sharpened.
His vision clarified like a lens focusing. His muscles responded before his brain finished issuing commands. Where before he'd matched Selina move for move, now he was a half-beat ahead—seeing her strikes not as they launched but as they formed, reading intention in the tension of her hip flexors.
Her kick passed three inches from his face. He didn't blink.
The follow-up came faster: roundhouse, side kick, spinning back kick, a punishing rhythm meant to overwhelm. Jack flowed around each strike like water parting for stone. His body bent at angles that should've been impossible, spine curving in ways that made Selina's excellent flexibility look merely human.
Slow.
Everything was so slow.
"Come on," Jack murmured, weaving between two consecutive strikes without shifting his feet. "I know you can do better."
"Son of a—"
Infinite Superposition—Two-fold.
This time he didn't wait.
Selina's leg was still chambering for another kick when Jack stepped forward, dropped his shoulder, and drove it into her collarbone with rotational force that started in his heel and terminated in her skeleton. A shoulder check—technically a technique she knew—but amplified, accelerated, delivered with timing she couldn't match.
Selina flew backward.
Her shoulders hit the concrete wall with a meaty thud. She slid down, catching herself on one knee, and Jack watched the color drain from her face as the impact registered. Her left arm hung at a strange angle. Not broken—probably—but the joint had absorbed enough force to make her eyes water.
"What..." She sucked air through her teeth. "What the hell are you?"
Jack considered several answers. Transmigrator. Cheater. Walking bug in the universe's code.
"Well," he said instead, "I'm definitely not a cat person."