Fantastic Batman Secrets That You May Not Be Aware of

Batman Arkham Asylum There is a hidden room in the Arkham mansion that has plans for the sequel 

Batman Arkham Asylum was chock full of secrets that hinted on a sequel, of course many player were quite oblivious to that fact. In a hidden room in the Asylum, there is a room and after applying three sprays of the explosive gel on a wall, players can enter and see blue prints, pictures and plans for the sequel, Batman: Arkham City.