Cugel the Clever
Foreverness writes that the editor came up with the title “The Eyes of the Overworld” and that according to Vance that didn’t make sense, then it should have been “The Eyes of the Underworld”. (ref)
Became part of the novel The Eyes of the Overworld (which was later re-titled as Cugel the Clever).
Republished in Cugel the Clever, Spatterlight, 2012