Capture and lock up Harley Quinn

Complete a combo of 20 moves (any play mode)

Face your biggest fears and keep your sanity

Gain access to Administration after it is locked down by the Joker

Survive the nightmare of the Scarecrow's fear gas

Solve 10% of riddler challenges

Witness Cordelia and some other girl arguing.

Finish the game and return to the beginning.

Sneak through the underground passage without tearing your scarf.

String up one henchman and drop him to surprise a second (any play mode).

Survive the onslaught from the deformed Joker henchman

Take down Zsasz in the Patient Pacification Chamber

Complete File R-00: Guard Duty.