Battle has been joined at the end of bk 4; now the composer displays its progress through the exploits of a single great hero. In a sense Diomedes reminds us of the absent Akhilleus, combining a certain reserve and prudence with something of the other's demonic quality after Patroklos' death. That, and Athene's continuous support, lead by almost inevitable stages to this Book's special theme of the wounding of gods. After an initial run of lesser victims he is confronted by Pandaros and Aineias, of whom he kills one and wounds the other; Aphrodite enfolds her son Aineias in a new version of the scene in bk 3 where she rescued her favourite Paris; encouraged by Athene, Diomedes attacks and lightly wounds her. Her comforting by Dione is a brilliant interlude, but the dominant theme of attacking gods reappears as Apollo himself has to repulse Diomedes and summon Ares to help the Trojans. Athene and Here decide to intervene and descend to the battlefield; Athene joins Diomedes in a spear-attack on Ares, who is severely wounded and, as Aphrodite had done, retreats to Olumpos where Zeus reluctantly has him cured.

The physical damage to the two immortals is a startling idea; but one of them is the antithesis of war, the other its most contemptible exponent. No other deity could suffer thus, though Dione comforts Aphrodite with historical precedent.