Half-Olympian son of Poseidon by Tyro daughter of Salmoneus. Conceived when Tyro loved the river-god Enipeus; Poseidon took Enipeus's form and lay with her on the river-bank, the waves rising in a dark mountain over them (Hom. Od. 11.243-244 — among the most lyrically-detailed conception-passages in early Greek epic). Twin of Pelias; both born and exposed; recovered into the household of Tyro and her stepmother Sidero. Pelias killed Sidero at the altar of Hera (sacrilege Hera would later avenge through Medea). Quarreled with Pelias over the kingship of Iolcus; expelled, traveled to Messenia, founded the kingdom of Pylos. Married Chloris daughter of Amphion of Orchomenos; fathered twelve sons (the most famous being Nestor) and one daughter, Pero. Refused to purify Heracles for the murder of Iphitus son of Eurytus (only Deiphobus son of Hippolytus would do so); in retaliation, Heracles attacked Pylos and killed Neleus and eleven of his twelve sons — only Nestor (away in Gerenia at the time) survived. Hesiod fr. 35 records that Hades himself joined the battle on Neleus's side and was wounded by Heracles in the shoulder, the only known Iliadic-tradition wounding of an Olympian by a mortal hero. The Mycenaean palace-site identified as Nestor's palace by Carl Blegen's 1939 excavations preserves Linear B archives of the late Mycenaean Pylian kingdom — providing one of the firmest archaeological-textual anchors for the heroic-age genealogy.