Polypheides or Polyphides (Ancient Greek: Πολυφείδης) is a Melampodid seer, son of Mantius and brother of Cleitus. After Amphiaraus' death Apollo made him the best seer among mortals; he dwelt at Hyperesia and fathered Theoclymenus, who later joins Telemachus. A separate Sicyonian lord of the same name shelters the young Atreids in a different tradition.
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I.Melampodid seer
Homer traces the house from Melampus of Pylos through Antiphates and Mantius. Mantius begot Polypheides and Cleitus; Dawn snatched Cleitus for his beauty, but Apollo made Polypheides a prophet surpassing all mortals once Amphiaraus lay dead.
Wroth with his father, Polypheides removed to Hyperesia, where he dwelt and prophesied to all men. His son Theoclymenus, of the same seer-line, later finds Telemachus at Pylos and sails with him to Ithaca.
II.Pherecydes' variant
Pherecydes, cited in the Odyssey scholia, gives a slightly different life: Polypheides married Aechme daughter of Haemon and settled at Eleusis, where Theoclymenus and Harmonides were born to him. The atlas keeps Homer's Hyperesia dwelling as the primary frame.
III.Homonyms
A second Polypheides is lord of Sicyon, to whom Agamemnon and Menelaus were entrusted after Atreus' murder before he sent them on to Oeneus. That Sicyonian host is not this Melampodid seer.