Medusa

Medusa is a Pre-Hardmode enemy found underground in miniature Marble biomes that inflicts the Stoned debuff if the player is in sight. As soon as the debuff wears off (around 3-4 seconds), Medusa will reapply the debuff until the player is killed or out of sight unless she's being attacked, making her very difficult to fight. She drops around 10 silver coins upon death, as well as a chance of a Medusa Head to drop. A player can predict when she is about to apply her stoned debuff by looking at her sprite which changes into a hunched over, uglier form.