Joker (Earth-6531)

"Isn't it funny how one little encounter can cleave off little pieces of your past, deform your memories and persona until you rethink your whole identity — and as you realize how foolish it all is — your laughter reverberates off the walls of your own emptiness?"

- - Joker to Bruce Wayne

The Joker is an unstoppable criminal, serial killer, terrorist, and the greatest enemy of the Batman. Formerly a patient by the name of "John Doe" who resided in Arkham Asylum, Gotham City, where he helped Bruce Wayne escape in the wake of the appearance of the Children of Arkham, and later on escaping to join the Pact.

Early Life
With a past shrouded in mystery and unknown, the Joker was named only "John Doe" by the staff of Arkham Asylum. What is known is what he claims, such as having wakened up alone at an Arkham cell, and that other patients became scared of him, such as Victor Zsasz. However, some staff, such as Doctors Joan Leland and Doctor Harleen Quinzel, Doe showed signs of progress and recuperation for his insanity.