[[WMG: It was the events of Eric (and the end of Sourcery) that resulted in Rincewind's Immortality and temperment.]]
Rincewind was cast into and STUCK in the [[DarkWorld Dungeon Dimensions]] and then by freak accident summoned and reversed summoned through a SummoningRitual that gave him demonic powers. Hence, his extreme Post Traumatic Stress Disorder that he is known for is first seen in this book; and the details of the summoning combined with having been PlaceBeyondTime when Literature/{{Discworld}} was created changed his metaphysical state.

[[WMG: Eric returned home at the end.]]
* If Rincewind [[spoiler: ended up back in Ankh-Morpork,]] then Eric must have made it out safe too! Whether or not he practices demonology remains a mystery.
** Probably not, given that he isn't heard of later.