Gorgons
Monstrous sisters with snakes for hair, tusks like boars and lolling tongues. The only mortal one of the three was Medusa. She had the power of turning to stone whoever looked at her, or whomever she looked at (the myth can be interpreted both ways). The hero Perseus, defending his mother from the unwanted advances of King Polydectes of Seriphos, swore to bring him Medusa's head.