Medea's Help, and a Homecoming Built on Betrayal

King Aeetes of Colchis, unwilling to give up the fleece, set Jason a further set of tasks he expected to be fatal: yoking a pair of fire breathing, bronze hoofed bulls to plow a field, sowing the field with dragon's teeth that sprang up as armed warriors, and getting past the sleepless dragon that guarded the fleece itself. Jason succeeded at each only with help from Aeetes's own daughter Medea, a priestess of Hecate skilled in magic, who fell in love with him at the goddess Aphrodite's prompting and gave him an ointment to protect him from the bulls' fire, instructions for turning the sown warriors against one another, and a drug to lull the dragon to sleep so the fleece could be taken.

Medea left Colchis with Jason and the Argonauts, and later tellings make her betrayal of her father complete: in the version most often followed, she killed and dismembered her own brother Apsyrtus and scattered his remains behind the fleeing ship, forcing the pursuing Aeetes to stop and gather them for burial rather than continue the chase. The Argonauts eventually returned to Iolcus with the fleece, and Medea again used her craft against Pelias, persuading his own daughters to kill and dismember him in a promised rejuvenation ritual that never restored him, a final act of vengeance that secured Jason no throne of his own and left the couple to a marriage in Corinth that later myth remembers ending in Medea's own act of vengeance against Jason himself.