In Greek mythology, Perseus killed Medusa, the only mortal Gorgon.
Medusa was a monster whose gaze could turn living beings to stone. Perseus was sent to obtain her head, a task that seemed impossible because looking directly at her was fatal. The gods aided him: Athena provided a polished shield, Hermes supplied a sword or sickle, and other divine gifts helped him approach and escape.
Perseus avoided Medusa’s gaze by using the reflection in Athena’s shield. After decapitating her, he placed the head in a protective bag. The blood from Medusa’s body produced the winged horse Pegasus and the warrior Chrysaor in later traditions.
Perseus later used Medusa’s head as a weapon, including against the sea monster threatening Andromeda and against Polydectes. A common mix-up is treating all Gorgons as mortal; in the best-known tradition, Medusa alone could die, while Stheno and Euryale were immortal.