Cursed Skull is a Trinket in original Binding of Isaac and Rebirth.
If Isaac takes damage with 1/2 red heart remaining, he will be teleported to the last cleared room he was in.
The effect will always be activated if the player has no Heart Containers, which means ??? with this trinket will always be teleported back to the previous room whenever he takes damage.
- Because of this, the Cursed Skull is considered as the most useless trinket in the game.