Athena goes to the Trojans to tempt one of them to break the truce by shooting an arrow at Menelaus. Her ploy is to convince him it will give him glory (which even Agamemnon alludes to when he says "Some Trojan or Lycian archer has wounded him with an arrow to our dismay, and to his own great glory." Then when the Trojan archer does shoot, Athena doubles back to Menelaus to prevent the arrow from killing. The shooting of the arrow is enough to mean the Trojans first broke the truce, so all the curses on the truce breaker will fall on Troy.
"Tydeus did not shrink thus, but was ever ahead of his men when leading them on against the foe...."
Agamemnon says this to Diomedes. His father was Tydeus who, having been exiled for murder, fled to Argos where he met one of the cursed sons of Oedipus, Polynices, who had been banished from Thebes by his brother Eteocles. Tydeus and Polynices became brothers in law by marrying two of the king's daughters. Tydeus then became part of the coalition to take back Thebes for Polynices. Neither man survived the battle.
"First Antilochus slew an armed warrior of the Trojans...."
As always in the Iliad, honor is everything, and the Trojans must always be slighted, so the Greeks get first blood.
