A Greek hero of the Trojan war, Son of Tydeus. He is the youngest of all of the Greek kings but is described as the most valiant, is considered the greatest warrior second only to Achilles, and is only even contested in his wisdom by the much older Odysseus. He is the favored warrior of Athena during the Trojan war and even went as far as to injure Ares, the god of war, while infused with her power. He sailed to Troy with the third greatest fleet of ships bested only by the fleets of the also much older Agamemnon and Nestor. He is the king of the city of Argos. Pretty much one of the most badass dudes in mythology.
As Diomedes spoke he sprang from his chariot, and his armour rang so fiercely about his body that even a brave man might well have been scared to hear it.