The Indigo Man appears in Chapter 2, when Bod and Scarlett visit the Sleer for the first time. The Indigo Man doesn’t seem to be a living being, but rather an image projected by the Sleer to scare off greedy treasure-seekers. He’s a huge guy with purple (indigo) tattoos all over its face. It sounds very similar to the faces of the Sleer’s three heads. The Indigo Man is only visible when there’s extreme fear in the air. When Bod and Scarlett realize this and stop being afraid, the Indigo Man vanishes. Phew.