Ifigenia in Aulide

The Greek army is gathered at Aulis, ready to sail for Troy, but the winds fail. The seer Calchas reveals that the goddess Artemis is angry and demands a sacrifice. King Agamemnon’s daughter, Ifigenia, must die for the fleet to depart. Torn between duty to Greece and love for his daughter, Agamemnon initially uses a ruse to bring Ifigenia to Aulis; he claims she is to marry Achilles. When Ifigenia and her mother Clitennestra arrive and learn the truth, they are devastated. What hero might intervene to save Ifigenia from the altar of sacrifice?