Shredder developed a plan to defeat the Turtles by mutating members of this street gang, so that they would have abilities parallel to the Turtles'. Bebop and Rocksteady both volunteered to undergo the procedure (though neither was particularly aware of what it would entail) with the promise that it would let them get revenge on the Turtles. Bebop was mutated into a human warthog, and Rocksteady into a rhinoceros. However, though the transformation did make them larger and stronger, they remained incompetent simpletons, and completely inept at stopping the Turtles or carrying out Shredder's plans. For most of the series they were employed for comic relief purposes. In one episode of the series, Bebop was shown to have kept a pet turtle, which got mutated into the evil turtle Slash.