Agonizer

Agonizers are stationary enemies that spew bullets randomly in all directions, pausing for a short duration after each burst of bullets. Upon death, they explode.

Agonizers are often positioned in the center of large rooms to cover the most space with their attacks.

Trivia

 * Prior to the Supply Drop update, Agonizers could be instantly killed through contact with pits, which was nearly impossible under most circumstances due to their immobility.
 * In the final scene in The Bullet's past, a gleeful Agonizer can be seen in the group of monsters, rolling back and forth in the grass.
 * Agonizers are currently the only enemy encountered outside boss fights which are completely immobile on their own.
 * The design may be a reference to the stone masks (specifically Kars') from JoJo's Bizarre Adventure.