professor M. A. R. Barker, a scholar of ancient languages, had spent decades crafting a fantasy world called Tékumel, writing thousands of pages of histories, describing its culture, and even constructing its languages. He served as adviser to the university's wargaming club, where a club-mate and role-playing game player Michael Mornard showed him Dungeons & Dragons. Barker first self-published 50 copies of his own role-playing game, Empire of the Petal Throne in 1974, the same year that Dungeons & Dragons was published. This version is now referred to as "Manuscript edition". Also, "Empire of the Petal Throne" is a synonym for the Tsolyáni Empire in game. Barker also wrote another game based in Tékumel: a combat-oriented board game, War of Wizards in 1975."
Empire of the Petal Throne influenced Dave Arneson and Gary Gygax, who were impressed with the game. Barker made his commercial game-design debut at Tactical Studies Rules, Inc., the publishers of Dungeons & Dragons, with Empire of the Petal Throneboxed set in 1975. TSR published Barker's game and setting as a standalone game, rather than as a "supplement" to the original D&D rules. The game brought a level of detail and quality to the concept of a campaign setting which had previously been unknown in the nascent RPG industry's publications. The game was the subject of articles in early issues of Dragon magazine, but factors such as inconsistent support from TSR led to its decline in popularity. TSR was locked into a deal that made the financial end of the game unpalatable to them. They had agreed to pay a "finder's fee" on sales in addition to royalties as well as to certain expensive overrides. As a result, the product was more expensive and thus less profitable.
Empire of the Petal Throne's setting, Tékumel, used a mixture of fantasy, science fantasy and science fiction backgrounds.
Game design
Empire of the Petal Throne introduced the concept of critical hits with a 20-sided die. Using these rules a player who rolls a 20 on a 20-sided die does double the normal damage, and a 20 followed by a 19 or 20 counts as a killing blow. According to M.A.R. Barker, "this simulates the 'lucky hit' on a vital organ."
Reception
Rick Mataka reviewed Empire of the Petal Throne in The Space Gamer No. 4. Mataka commented that "So, if you have enjoyed Dungeons and Dragons in the past, then this is the game of the future. Empire of the Petal Throne is the 'now' game for all fantasy gamers."