In Homer's Odyssey, Amphimedon is the Ithacan son of Melaneus and one of Penelope's suitors. He grazes Telemachus with a spear in the final fight in Odysseus' hall, then in the Underworld recounts the slaughter of the wooers to Agamemnon's shade — recalling that he once hosted the son of Atreus on Ithaca.
Adapted from Wikipedia, "Amphimedon" · CC BY-SA 4.0
I.Last fight in the hall
Apollodorus counts Amphimedon among the twelve wooers from Ithaca itself. In Odyssey 22, when the bow has already laid most of the company low, he stands with Agelaus son of Damastor and the other bold survivors; retreating before Odysseus' party he gives a glancing blow to Telemachus' wrist, then falls to the prince shortly afterward.
II.Shade in Hades
In Odyssey 24 Agamemnon's spirit recognizes glorious Amphimedon, son of Melaneus, who had been his host while dwelling in Ithaca, and asks what doom brought him and his companions down. Amphimedon's shade then tells the whole tale of Penelope's web, the contest of the bow, the mnesterophonia, and the punishment of the disloyal maids — the fullest suitor-voice in the Nekyia.
III.Homonym care
The atlas id amphimedon-ithaca is the Melaneid Ithacan wooer alone. Not to be merged with other Homeric or handbook Amphimedons; the Wikipedia stub and Odyssey template treat this Ithacan as the mythic bearer of the name.