Hellbat

Hellbats are large Bats found only in The Underworld. They are pesky creatures that like to push you into lava, and can kill characters who are using early game gear. Though they cannot fly underwater or through Lava, they take no damage from making contact with either.

Trivia

 * Its name and area of appearance are likely references to the saying "like a bat out of Hell."
 * When a player kills their 50th Hellbat while in the underworld, several Hellbats will spawn simultaniously.