You can get fiery rooms without the cloak! However, it will cost you a life... To pass through the fire unscathed, enter the room. Its heat will be unbearable, and your character will be placed in mirrored room. Once there, touch one of the wall mirrors. You character will die, but when you continue the action he will be in the fire-filled room and he won't feel the heat!
Hit select when in any room, it well hint you of any secrets.