Fan Casting Joker in Batman: Arkham Asylum

Pretending to stumble and trip, the Joker bashed his guard in the face with the back of his head when the guard demanded him to get up. He then used his handcuffs to strangle the guard, forcing the doctor to unhook the Joker to save the guard. Joker strangled the guard to death before the doctor could save him and, once his cuffs were off, fatally kicked the doctor down, breaking his ribcage and killing him as well. Joker signaled to Harley, who opened up the adjacent electrical doorway, allowing the Joker to access the cell controls.