Turn her into Batman.

As the impish Mr. Mxyzptlk basked in his amusement, his eyes twinkled with a mischievous idea. He looked at Batwoman, still suspended by his ethereal chains, and a devilish grin spread across his face.

The imp snapped his fingers. Instantaneously, the celestial chains that bound her started glowing, releasing an energy that began to rewrite her physical structure.

The feminine contours of her suit started to vanish, replaced by a more masculine outline, the torso expanding, and the hips narrowing. Her suit's crimson bat emblem darkened into the iconic shadowy black of the Batman's symbol. The logo pressing down on her breasts, the soft tissue slowly dissipating with each panicked breath. The fat from her depleting mammary glands turning into hardened pectorals.

Her waist began to broaden, muscular definition appearing beneath the bat suit's armor, replacing the lean frame she possessed. The suit expanded around her chest and shoulders, filling out as her frame became broader and more solid, resembling the robust silhouette of Batman. Bulk filled out her abs, building over her previously slim stomach.

Her ass began to tighten under the influence of Mxyzptlk's magic. The softness of her heart shaped butt hardened, consolidating into packed in musculature. Her thighs following suit, any and all fat turning into muscle.

At the same time, her arms, once lithe and athletic, began to bulk, her biceps and triceps bulging with newfound power. Testosterone like she'd never felt before ran through her veins, leaving her with newfound strength. Her hands became larger, fingers slightly longer and stronger.

Her face, once delicate with soft features, started to shift. The soft curves became more angular, her jawline squaring off, growing harder and more pronounced to mimic Batman's stern visage. Her lips, once full and defined, morphed into a firm, straight line akin to the Dark Knight's slight pout. Her nose became more prominent and structured, akin to Bruce Wayne's strong profile. She blinked a few times, her emerald eyes replaced with ocean blue irises. A wave of five o-clock shadow coating her jaw.

Her hair, a vivid auburn, shrank away, replaced by the dark, short-cut tapered style that Bruce Wayne was known for. Her eyes, once round and expressive, became narrower and more piercing, reflecting Batman's intense, calculating gaze.

"I-I'm... Batman?"

She reached for her throat, feeling the presence of a new Adam's apple. Her voice, once clear and high pitched, deepened into the gruff, authoritative tone that was Batman's trademark.

"Not quite yet, yer not!"

The imp teased.

"What do you-GRGh!"

Kate groaned, a sudden churning sensation building in between her legs. What was left of her female anatomy convulsed as her womb and ovaries dissipated into nothingness. Her face turned beet red as she hopelessly shot her hands to her crotch. There was no way she was going to get this suit off in time. And even if she could, there was nothing she could do to stop what was coming.

"W-why!"

Kate cried, the burgeoning head of a freshly developed member forming between her walls, grazing against them on its way out. Brushing against her boxers and erupting out of her former slit with a full shaft and all. Her brand new batarang dangling between her beefier, muscular thighs. The noticeable bulge firmly erect beneath her batsuit.

"I-You-you gave me a dick?!"

Kate snarled.

"All in good fun, lass-er-lad!"

Mr. Mxyzptlk grinned, indulging in her visceral reaction.

Kate's batsuit finished converting to Bruce's batsuit, the cowl sealing itself over her now short black hair, her utility belt shifting shades to a brushed gold color. Her high heeled combat boots lost their height and became regular combat boots, a new array of gadgets appearing on her belt and gauntlets she didn't recognize.

"Good fun?! Change me back, you miserable imp!"

Kate shouted, Bruce's tone leaving her lips, coming out more gruff and demanding.

"Hmmm... Nah!"