In his first stage, he acts identical to Pin, diving at the player and firing a IPECAC-based shot.
In his second stage, he is a skeletal worm with intense attacks, such as:
- Firing 2 Brimstone beams at wherever Isaac is.
- Firing a Brimstone beam that circles the room, which goes moderately fast.
- Sticking its skeletal bottom in the air, which fires a white cluster of tears that can cover the room, similar to Monstro's leap attack.
It is recommended to move and stick close to the wall, as this boss can be incredibly difficult.