Bombshee

The Bombshee is an enemy added in the Supply Drop Update.

Bombshees follow other enemies around, frequently emitting a short-ranged shriek that destroys the player's bullets.

If a Bombshee is the only enemy remaining in a room, it will launch towards the player and self-detonate.

Trivia

 * The Bombshee's name is a portmanteau of the words Banshee, a female spirit whose screeches were said to warn of impending death, and bomb, more specifically a bombshell.
 * Bombshee's sprite could be seen embedded in the top right of Wallmonger before Bombshee was added as a separate enemy during the Supply Drop update.
 * Bombshee could also be seen in one of the default screenshots on Steam.