4 books in series

Greyhawk Classics

Greyhawk Classics is a 4-book series with 4 primary works first released in 1999 with contributions by Paul Kidd, Thomas M. Reid, and Keith Francis Strohm.

White Plume Mountain: Greyhawk Classics
Descent into the Depths of the Earth
The Temple of Elemental Evil
The Tomb of Horrors