Jason and Medea
Medea's role began after Jason arrived from Iolcus to Colchis, to claim his inheritance and throne by retrieving the Golden Fleece. In the most complete surviving account, the Argonautica of Apollonius, Medea fell in love with him and promised to help him, but only on the condition that if he succeeded, he would take her with him and marry her. Jason agreed. In a familiar mythic motif, Aeëtes promised to give him the fleece, but only if he could perform certain tasks. First, Jason had to plough a field with fire-breathing oxen that he had to yoke himself. Medea gave him an unguent with which to anoint himself and his weapons, to protect him from the bulls' fiery breath. Then, Jason had to sow the teeth of a dragon in the ploughed field (compare the myth of Cadmus). The teeth sprouted into an army of warriors. Jason was forewarned by Medea, however, and knew to throw a rock into the crowd. Unable to determine where the rock had come from, the soldiers attacked and killed each other. Finally, Aeëtes made Jason fight and kill the sleepless dragon that guarded the fleece. Medea put the beast to sleep with her narcotic herbs. Jason then took the fleece and sailed away with Medea, as he had promised. Apollonius says that Medea only helped Jason in the first place because Hera had convinced Aphrodite or Eros to cause Medea to fall in love with him. Medea distracted her father as they fled by killing her brother Absyrtus. In some versions, Medea is said to have dismembered his body and scattered his parts on an island, knowing her father would stop to retrieve them for proper burial; in other versions, it is Absyrtus himself who pursued them, and was killed by Jason. During the fight, Atalanta, a member of the group helping Jason in his quest for the fleece, was seriously wounded, but Medea healed her.
According to some versions, Medea and Jason stopped on her aunt Circe's island so that she could be cleansed after the murder of her brother, relieving her of blame for the deed.
On the way back to Thessaly, Medea prophesied that Euphemus, the helmsman of Jason's ship, the Argo, would one day rule over all Libya. This came true through Battus, a descendant of Euphemus.
The Argo then reached the island of Crete, guarded by the bronze man, Talos (Talus). Talos had one vein which went from his neck to his ankle, bound shut by a single bronze nail. According to Apollodorus, Talos was slain either when Medea drove him mad with drugs, deceived him that she would make him immortal by removing the nail, or was killed by Poeas's arrow (Apollodorus 1.140). In the Argonautica, Medea hypnotized him from the Argo, driving him mad so that he dislodged the nail, ichor flowed from the wound, and he bled to death (Argonautica 4.1638). After Talos died, the Argo landed.
While Jason searched for the Golden Fleece, Hera, who was still angry at Pelias, conspired to make Jason fall in love with Medea, who Hera hoped would kill Pelias. When Jason and Medea returned to Iolcus, Pelias still refused to give up his throne. So Medea conspired to have Pelias' own daughters kill him. She told them she could turn an old ram into a young ram by cutting up the old ram and boiling it. During her demonstration, a live, young ram jumped out of the pot. Excited, the girls cut their father into pieces and threw him into a pot. Having killed Pelias, Jason and Medea fled to Corinth. This is much like what she did with Aeson, Jason's father.
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