from the Introduction:
Tékumel is a place with the politics and intrigue of the Roman Empire, the religions of ancient India and pre-Columbian Mesoamerica, the magic of the Arabian Nights, the monsters and demons of the Cthulhu mythos, plus ancient ruins containing the technology of a good space opera thrown in just to keep things interesting.
This book adapts The Fantasy Trip (TFT) rules from Metagaming Concepts for adventures on Tékumel. The TFT ruleset is needed to play this game. Alternatively, Legends of the Ancient World (a free RPG similar to TFT, from Dark City Games or Heroes and Other Worlds (a new TFT inspired game from Christopher Brandon) are suitable substitutes.
There is very little setting information in this sourcebook, aside from creatures, spells and some character details. A more detailed source of Tékumel setting information is necessary to use this material for its intended purpose: Tékumel gaming.