| The Cellar|
The Catacombs (Double Trouble)
The Depths (Normal Enemy)
Boss Challenge Room
Pin is largely unchanged from original. His overhaul though is that Pin now better tracks the player, and that it no longer damages itself.
- Sometimes, a Spitty, conjoined spitty or round worm can be in the middle of the room at the start of the battle.
- Pin will propel himself out of the ground, attempting to ram the player.
- Four tears will shoot diagonally from where Pin emerged.
- Occasionally, it will stick its head out of ground in order to fire an explosive projectile.
Black: Is larger and fires six shots instead of an explosive projectile.
- Pin was added in the Wrath of the Lamb DLC for the original Binding of Isaac.
- Pin is based off the pinworm, an internal parasite.
- Pin is likely a reference to Lanmola, a boss from The Legend of Zelda: A Link to the Past; as nearly all attacks are the same.
- Pin's health bar does not accurately display the total health of the boss. You only need to reduce Pin down to approximately 1/8th of its total health to kill it.