Medusa received help. He received a mirrored shield from Athena, gold, winged sandals from Hermes, a sword from Hephaestus and Hades's helm of invisibility. Since Medusa was the only one of the three Gorgons who was mortal, Perseus was able to slay her while looking at the reflection from the mirrored shield he received from Athena. During that time, Medusa was pregnant by Poseidon. When Perseus beheaded her, Pegasus, a winged horse, and Chrysaor, a giant wielding a golden sword, sprang from her body. Jane Ellen Harrison argues that "her potency only begins when her head is severed, and that potency
Perseus she had before been promised. At the wedding a quarrel took place between the rivals, and Phineus was turned to stone by the sight of Medusa's head that Perseus had kept. Andromeda ("queen of men") followed her husband to Tiryns in Argos, and became the ancestress of the family of the Perseidae who ruled at Tiryns through her son with Perseus, Perses. After her death she was placed by Athena among the constellations in the northern sky, near Perseus and Cassiopeia. Sophocles and Euripides (and in more modern times Pierre Corneille) made the episode of Perseus and Andromeda the subject