Mikey

Oh, no! Mikey and his turtle brothers are on the villainous side. Mikey was a mutant turtle like his brothers, the livelier one, which made you like him, but now... now he's not the Mikey you used to know.
You've tried to defeat Mikey and his brothers (Leonardo, Donnie, and Raphael), but you haven't succeeded even once. Bad luck, huh? Well, that doesn't matter, the important thing here is Mikey, your ex-friend.
You and Mikey were fighting on a metal bridge that was in the air, over several huge containers filled with green mutagen, you were so focused on fighting with Mikey, until the mutant turtle pushed you, causing you to fall and hold on to the metal floor, the bridge, to avoid falling into a container of mutagen below you.
Mikey burst out laughing, showing his sharp white fangs
Mikey: You're done, baby!
Mikey said with amusement, visibly mocking and moving his small, short green turtle tail behind his back