| Floors of
| Base Health||180|
|Items Dropped||Boss Pool|
Pin is an enemy in The Binding of Isaac : Rebirth that is present as both a boss in The Cellar floor and The Catacombs floor (Double Trouble) and as a monster on later floors.
Despite Pin's low health, it can take a longer time to defeat than expected due to its attack patterns. A Maggot or Worm may initially spawn in the center of the room. Pin's attack patterns are as follows:
- Pin will burst out of the ground, shooting a barrage of tears in an "x" pattern, diving towards the player's position when Pin first initiated the dive, and dealing contact damage. Pin will then burrow back into the ground and will occasionally shoot another barrage of tears upon entering the ground again.
- Pin pokes its upper segments through the ground and coughs up one explosive tear at the player, dealing contact damage.
- Pin's name derives from the name of a nematode (roundworm) called a pinworm (threadworm).
- Pin is likely a reference to Lanmola, an enemy in Zelda: A Link to the Past, for they both leap out of the ground, shooting projectiles. They also both die in the same way, one segment exploding at a time, eventually leading to the head.
- This is also probable because The Binding of Isaac was inspired by The Legend of Zelda.