How does the author use foreshadowing in The Waste Lands?

Stephen King's novel "The Waste Lands" is the third book in a series that follows Roland's quest for the Dark Tower. Roland and his companions hope that by reaching this tower, they can set right the terrible changes that are occurring in Roland's world. Throughout their journey, Roland and his companions encounter insane mechanical bears, sick pirates, and a monorail train on a suicide mission. The novel ends with much left unfinished and the characters in a precarious situation.