Medusa

Medusa is a Pre-Hardmode enemy, found at cavern level. Ordinarily a relatively fast-moving melee attacker, Medusa have the ability to inflict the Stoned debuff through their gaze. The debuff's onset is marked by the Medusa's snake hair lashing out red tongues, giving players a split-second to turn away. Players facing the Medusa when the animation completes will be turned to stone, completely immobilizing them and increasing fall damage.

Trivia

 * Similar to Frankenstein, Medusa is erroneously named; in mythology, Medusa was a single individual, not the name of her species. The correct term for snake-haired women capable of petrification would be Gorgons.