Outside the temple, the king and High Priest join with Neptune's priests to pray that the god will be kind and merciful. Arbace brings news that Idamante has killed the monster. Idomeneo is now worried that Neptune will want even more revenge. Idamante enters in sacrificial robes, saying he understands his father's terrible worries and he is ready to die., Idomeneo says a tragic goodbye to his own son and is about to kill him, when Ilia steps forward and offers to die instead. Neptune now changes his mind. We hear his voice saying that if Idomeneo gives up being king and lets Idamante and Ilia rule as king and queen, he will forgive. Everyone is happy except Electra, who wants to die. Idomeneo says that Idamante and his bride are the new rulers. The people call upon the god of love and marriage to bless the royal pair and bring peace.