Tried-and-true dungeon building ideas, guidelines, and tactics are incorporated into Dungeon Builder's Guidebook, a 64-page accessory that will be appreciated by experienced and novice DMs alike.

One of the nicest features of this accessory are a collection of 78 geomorphs, sections of dungeon that can be joined to each other directly or via connecting passageways (a ruin/tomb geomorph appears below). Six sorts of dungeon environments--mine/natural cavern, interdimensional, aerial, castle, ruin/tomb, and underwater--are provided, along with guidelines on how to use them. Each type has a "founding" geomorph that provides an outside or overall view of the dungeon, and a "focus" geomorph, or the initial dungeon section from which the others of its type can be reached. Each focus geomorph is fully keyed with monsters, traps, and treasure.

Other features of Dungeon Builder's Guidebook include an "Autodungeon Engine" random dungeon generator; general characteristics and (brief) encounter tables for each dungeon type; a section on traps along with a trap generator; a section on dungeon permutations; and sections on dungeon lore and approaches to design.

All-in-all, Dungeon Builder's Guidebook can be useful in many ways to many gamemasters, from a source of maps for experienced DMs who need a quick home for their monsters to a comprehensive how-to guide for DMs are just getting started. It rates a solid 6 on a 6-point scale.