Odysseus is the main hero of the story. In the first part of the story he is even the narrator. He faces many challenges most which are supernatural, and always bests those challenges like almost all epic heroes.
The Sirens are a perfect example of a shadow. Their main power is to pull out ones deepest desire. Odysseus knew of these powers and still Odysseus' strong will was not enough to deter their offers and persuasions. He was only not brought down by the sirens thanks to the help of his plan and his crew.
When Odysseus had finally returned home to Ithica Athena disguised him as a beggar. Since he was a beggar he could gather a lot of information he couldn't have as Odysseus being the famous hero he is. Athena provided much needed support to help Odysseus reclaim his position as king, his castle, and his wife.