In Greek mythology, Medusa (Greek: Μέδουσα, Médousa, "guardian, protectress") and some times known as the Gorgon, was a monstrous chthonic female character essentially an extension of an apotropaic mask whose gaze could turn on-lookers to stone. She was born of Phorcys and Ceto or in some cases, Typhon and Echidna (Pre-Titan gods). She had two sisters, Stheno and Euryale both of whom were immortal. Medusa on the other hand was not. They lived on an island at the end of the world.

In other versions she was a human with blonde hair and she had no sisters. She slept with Poseidon in Athena's temple, so Athena punished Medusa by turning her into a monster with hair made of snakes and is sometimes described to be half snake herself!

Perseus was instructed by his soon to be father to get the Gorgon's head. He used Hades's clap of invisibility, winged sandals from Hermes, a sword and a mirrored shield. After slicing her head off in her sleep, Pegasus and the giant Chrysaor sprouted. Perseus then flew off the island on Pegasus to escape her sisters who had woken up! He later returned to his soon to be father and turned him to stone with the gorgon's head.