Dreams

At many points, Shadow is given information about his journey through his dreams. Even before meeting Wednesday, Shadow dreams of the buffalo man who tells him a storm is coming. Before Wednesday gives him specific information about the war between the gods, a voice tells Shadow in a dream that the old gods are dying without belief. The dreams are a way for higher powers to get in Shadow's head and explain what's going on, without the interference of his waking mind. The dreams also lay the groundwork for upcoming events, so when the events happen, Shadow is better able to understand without question.

It also becomes clear that dreams have power for Shadow. When he dreams about thunderbirds, Wednesday calls to wake him and tell him he is sending out a signal. It seems all of the gods are able to access dreams, even the new gods...