Which Greek hero killed the Trojan archer Pandarus?

The Greek hero who killed the Trojan archer Pandarus was Diomedes.

Pandarus was a celebrated Lycian bowman fighting for Troy and leading troops from Zeleia. In Iliad Book 4, Athena—disguised as the Trojan Laodocus—persuades him to shoot Menelaus, breaking a truce that might have ended the conflict by returning Helen.

Pandarus later attacks Diomedes with a spear after his arrows fail to kill him. Athena protects Diomedes, and the Greek hero responds with a devastating spear thrust that strikes Pandarus in the face and kills him. Diomedes then confronts Aeneas, Pandarus’ companion, before Aphrodite rescues Aeneas from the battlefield.

A common mix-up comes from Pandarus’ role as an archer: he wounds Menelaus, but he does not kill him. Nor is the episode part of the later medieval romance in which Pandarus becomes a go-between for Troilus and Cressida. Homer’s Pandarus is a Trojan ally whose death occurs during Diomedes’ great battle sequence in Book 5.