The Greeks and heroes of Greek mythology

 

Jellyfish

She was a female ketone monster, turning into stone those who stared into her eyes. She was beheaded by Perseus, who then used her head as a weapon, until he gave it to the goddess Athena to put on her shield, the aegis. Since classical Greek antiquity, the image of Medusa's head is represented in the contraption that drives away the evil known as Gorgoneion. 

The three Gorgon sisters Medusa, Sthenus, and Euryale were daughters of Phorcys and Ceto, or sometimes of Typhon and Echidna, both chthonic monsters of the archaic world. This genealogy is shared by her other sisters, the Greas, as in the chained Prometheus of Aeschylus, who places both trinities far away, in the dreadful plain of Cystene.