Batman Arkham Asylum - Arkham Island, North Riddler's Challenges

Part 2: Follow the challenges detailed in this video while playing the game to get all the Riddler challenges, there are four types that this video reveals: Chronicle of Arkham - stone slabs to scan Patient Interview Tape - audio logs from the inmates Riddles - puzzles that the Riddler himself will present via radio or simply aligning the Riddler&symbol found on objects Riddler trophies - Green question mark collectibles scattered around in various places