Blaine is a pink monorail with a blue interior. He has a "sister" monorail, Patricia,(Who he let commit suicide). Blaine is going insane and the only thing that is keeping him from ending himself is his love for riddles.
Roland Deschain, Eddie Dean, Susannah Holmes, Jake Chambers, and Oy ride Blaine following the destruction of Lud (which Blaine caused). The ka-tet engage Blaine in a riddle competition. They win when Eddie tells a variety of jokes causing Blaine to shut down then die after he crashes.