The leader of the Mutants gang is nasty, brutal, and feral. He doesn't act like a civilized human. He defeats Batman in their first encounter, a hand-to-hand battle at the garbage dump. The Mutant leader ends up in custody though. Once in custody, the mayor decides to have a one-on-one conversation with him. The Mutant leader proceeds to rip the mayor's throat out with his teeth, chuckling as he does it. Batman tricks him into breaking out of his cell and following a vent out of the jail. He does not know that Batman is waiting to fight him with his entire gang watching. Batman ultimately defeats him and ends the reign of the Mutants gang on Gotham.
The New Batman Adventures
In the episode "Legends of the Dark Knight" Mutant Leader is voiced by Kevin Michael Richardson.