Solve 70% of Riddler challenges

Venture into Killer Croc's lair and come out alive

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

Defeat two Titan Henchmen at once

Solve 40% of Riddler challenges

Catch a Batarang (any play mode)

Face your biggest fears and keep your sanity

Complete one combat challenge without taking damage

Gain access to Arkham Mansion after it is locked down by the Joker

Solve 10% of Riddler challenges

Save all the doctors in Medical

Escape from Intensive Treatment to the island surface

Rescue the guards and henchman from the Joker toxin in Decontamination