 Their attempt to do so through capturing Shredder's adopted daughter Karai and holding her for ransom lead to their mutation into Bebop and Rocksteady after Karai escapes due to the Turtles' interference.In "Battle for New York," the Turtles's confrontation with the Kraang for the city occurred when they are unexpectedly joined by the Mighty Mutanimals, a rebel team of mutants.The two teams manage to thwart a Kraang plot to launch a mutagen missile, and then launch an attack on the Kraang portal so that the Turtles can infiltrate Dimension X and cure and free the mutated humans.