Agamemnon kills a deer sacred to Artemis and boasts of surpassing her, and her enraged winds trap the fleet until Calchas reveals that only Iphigenia's sacrifice will appease the goddess. Agamemnon lures his daughter to Aulis under the pretense of marrying Achilles, and despite a moment of regret, presses on after Menelaus reminds him the gods have already spoken. Iphigenia refuses Achilles's offer to defend her, choosing to face the altar with courage, and as her throat is slit the winds calm and Artemis accepts the sacrifice, securing Agamemnon's command. The fleets set sail at once, leaving Clytemnestra inconsolable on the shore, vowing that she will never forget this betrayal.