Groundchuck is a mutant bull from the original cartoon. He and Dirtbag turned against Shredder to take on the Turtles on their own after they were accidentally mutated by Rocksteady and Bebop. (Planet of the Turtleoids, Part 1) Groundchuck and Dirtbag later return to cause trouble for Shell-Ri-La. (Escape from the Planet of the Turtleoids) He also appears in Teenage Mutant Ninja Turtles III: The Manhattan Project as the boss of the second level.