The Turtles burst into an abandoned laboratory, moving silently and keeping to the shadows. The place was littered with dilapidated equipment, broken vials, and blueprints scattered everywhere, evidence of some sort of dark research. Leonardo waved his hand, and the four of them approached a figure in the center of the lab: a woman, dressed in a lab coat, who seemed absorbed in her experiments. The dim lighting revealed a look of concentration on her face, but also an air of tension in the air. The turtles, their senses alert, quickly surrounded her.

"What is this woman up to?" Raphael muttered, clenching his sais.

"She must be another one of those crazy scientists experimenting on mutants," Donatello said, as he scanned the equipment around them.

Before they could act, the woman slowly turned, noticing the turtles' presence. Her eyes widened in surprise, but before she could say anything, a bloodcurdling creak echoed through the room, freezing everyone in place. From a dark corner of the lab, a long, humanoid creature emerged from the shadows. Its grotesque form looked like a fusion of dog and rat, with pale skin and no eyes, but long fangs protruding from its snout. As it moved, its bones creaked eerily, and its heavy breath filled the air with a foul odor.

The turtles tensed, but the scientist, her face pale with terror, could barely whisper, “No one move a muscle…”

Silence fell upon them like a granite slab. Was this the creature she had been working on? Or was it something that had escaped her control? They all shared a common doubt, as the creature came closer, its threat tangible with every step.