Creep

Creeps are a series of spider-like enemies from the base game that cling to walls and attack using projectiles. Revelations added the following variants.

Stone Creep
Stone Creeps will try to line up with the player, periodically pausing to fire a single tear in the direction they face as they move. Stone Creeps are impervious to damage but die once all other enemies in the room have been defeated and/or all buttons have been pressed.