The Underdark sourcebook for the Forgotten Realms campaign setting of the 3.5 edition of the Dungeons & Dragons role-playing game.

[2] Cover art was by Sam Wood, with interior art by Kalman Andrasofszky, Matt Cavotta, Mike Dubisch, Wayne England, Matt Faulkner, Vance Kovacs, Vince Locke, Raven Mimura, Jim Pavelec, Vinod Rams, Richard Sardinha, Stephen Tappin, and Joel Thomas.

When asked how the designers dealt sorting through years' worth of publications on the Underdark to create a more definitive sourcebook, Jeff Quick responded: "I was the editor of Eric Boyd's exhaustively detailed 2nd edition sourcebook, Drizzt Do'Urden's Guide to the Underdark.

If you think your underworld design has recently gotten stale, or if you just want to remind yourself of the magic of Gary Gygax's original D-series adventures, then this book is what you're looking for.

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