Rusted Key

Rusted Key is a trinket.

Effects

 * Gives a 10% chance of changing the room drop reward to a key.
 * Opening chests and destroying tinted rocks, Slot Machines, or Fortune Teller Machines has a chance of adding a key to the rewards.

Trivia

 * In the original Binding of Isaac, this trinket was broken and didn't do anything. This was never fixed.