Russia, EarthNew York City
Brute strengthWeapons expertiseSuper-durability
Arms Dealer (formerly) Shredder's henchman (current)
Mutant RhinocerosFormer Human
Teenage Mutant Ninja Turtles: Portal Power
Formerly a Russian arms dealer, Ivan Steranko became the mutant rhinoceros known as Rocksteady.
Steranko appears as Rocksteady in Teenage Mutant Ninja Turtles: Portal Power and Teenage Mutant Ninja Turtles and as both his human and mutation in Teenage Mutant Ninja Turtles Legends.
A shady Russian arms dealer and collector with one glass eye, Steranko sells Shredder a missile launcher. He returns later to steal Shredder's helmet, the Kuro Kabuto.