Rocksteady is an antagonist of Teenage Mutant Ninja Turtles. He was originally a human Russian arms dealer with ties to Shredder and The Foot Clan named Ivan Steranko. He is now a mutant white rhinoceros who is one of Shredder's hench-mutants alongside his partner, Bebop. He made his debut in Enemy Of My Enemy.
Mutated by Shredder from Russian arms industry officer Ivan Steranko, Rocksteady swears allegiance to Shredder and agrees to team up with his partner-in-crime Bebop to form the dynamic duo of Bebop and Rocksteady. Our heroes need to use extreme caution when dealing with this mutated rock-headed rhino. He is the brains and brawn of the partnership and could deliver quite the feast to Shredder when the main course is Turtle Soup!