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Title: a narrator's tool
Review: This book is a great campaign buddy, as gives the reader excellent descriptions of underdark terrain and geography. When narrating an underground campaign, there are only so many variations of 'a cave,' or 'a tunnel,' that one can describe before the action gets tedious for the players. With this supplement, you get a range of interesting features, hazards, and ecologies to give it a more natural feel, for those of us with no real-life spelunking experience. Beyond that, it gives the usual WotC bundle of feats, PrC's, races, and spells. Most of this material is mediocre, but I still give the book 5*'s for being the only dungeoneering book out there that gives such a rich 'how-to' guide for making underground travel rich and interesting.
