Calchas

In Greek mythology, Calchas (/ˈkælkəs/; Ancient Greek: Κάλχας, possibly meaning "bronze-man"), son of Thestor, was an Argive seer, with a gift for interpreting the flight of birds that he received of Apollo: "as an augur, Calchas had no rival in the camp". He also interpreted the entrails of the enemy during the tide of battle.

It was Calchas who prophesied that in order to gain a favourable wind to deploy the Greek ships mustered in Aulis on their way to Troy, Agamemnon would need to sacrifice his daughter, Iphigeneia, to appease Artemis, whom Agamemnon had offended. The episode was related at length in the lost Cypria, of the Epic Cycle. He also states that Troy will be sacked on the tenth year of the war.

In the Iliad, Calchas tells the Greeks that the captive Chryseis must be returned to her father Chryses in order to get Apollo to stop the plague he has sent as a punishment: this triggered the quarrel of Achilles and Agamemnon, the main theme of the Iliad.

In Sophocles' Ajax, Calchas delivers a prophecy to Teucer suggesting that the protagonist will die if he leaves his tent before the day is out.

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