Sophocles refers to the prophecy of Helenus several times throughout the play, who claimed that the Trojan War can only be won if both Neoptolemus and Philoctetes go to Troy. While the prophecy is true, Odysseus keeping Achilles’s armor from Neoptolemus is a lie. According to myth, Odysseus and Ajax feuded over Achilles’s armor after his death, which led to Ajax’s suicide. Odysseus then gifted the armor to Neoptolemus. By inventing a conflict between himself and Neoptolemus, however, Odysseus is hoping the fake feud will win Philoctetes’s trust. Philoctetes hates Odysseus for marooning him on Lemnos, so Odysseus reasons that he’ll be more likely to trust Neoptolemus if he thinks that Neoptolemus hates Odysseus too.