Cracked Key

Cracked Key is a consumable item added in The Binding of Isaac: Repentance.

Effects

 * Acts as a single-use, allowing Isaac to create new rooms by using the key next to a wall where there would be no conditions that could prevent a (secret) room from spawning there. This is indicated by walls that have red door outlines on them.
 * These rooms are most commonly normal rooms, but have a chance to be various special rooms instead, including Devil Rooms, Angel Rooms, Shops, Treasure Rooms, or Sacrifice Rooms. The red rooms can be connected to Ultra Secret Rooms.