Who is Odysseus suppose to talk to when he goes to the underworld?

When Odysseus goes to the underworld, he is supposed to talk to the prophet Tiresias. Tiresias provides crucial guidance and insights about Odysseus's journey home to Ithaca, as well as the challenges he will face. Additionally, Odysseus encounters the spirits of other dead heroes and his mother, who also offer him valuable information and reflections on his life.