The three major male characters in Iphigenia in Aulis by Euripides are Odysseus, Agamemnon. and Achilles, and each represent far different ethical positions in the play. Odysseus is clever and unscrupulous, regarding everyone and everything instrumentally. His goal is to support Menelaus in the war against Troy, and thereby also strengthen his political connections and network of favors and obligations, despite being lord of a poor and remote island. Thus he is quite willing to see Iphigenia sacrificed.

Agamemnon appears in Euripides as he does in the Iliad as essentially weak and indecisive. He is torn between love of his brother Menelaus and love for his daughter whom the prophet Calchas has declared must be sacrificed. Unwilling to be honest, he invents the story of the marriage arrangement to dupe Clytemnestra and his daughter into being complicit with the sacrifice, and is strongly contrasted with the true heroism of Iphigenia herself. 

Achilles appears far more noble than Agamemnon in the play, concerned as much about the welfare of Iphigenia as about success in the war. Although he could have washed his hands of the whole issue once Agamemnon's duplicity was revealed, instead he takes responsibility for trying to save Iphigenia, even though eventually she makes the decision to be a willing sacrifice. He is portrayed as a strong and ethical character.