From the back cover:
One of the best parts of roleplaying is the opportunity to explore strange, new worlds. Now Chessboards: Planes of Possibility provides gamemasters with the first organized, flexible system for designing and evolving game environments. This fun-to-read book covers such topics as the various types of planes and their relationships, planar growth cycles, ways to planes, and several varieties of interplanar travel. For those using The Primal Order, it also includes expanded guidelines on planar use of primal energy, planar artifacts, and advanced interactions between planes and deities. Five sample metaplanes provide inspiration and illustrate important concepts. Usable with any roleplaying system, this reference work will give GMs the tools they need to create exciting new planes, run multiple settings in one campaign, or link several campaigns into one logically organized multiverse.