Four-player chess for themselves. As with regular chess, four-player chess begins with fortifications and the of pieces, but opportunities for capturing pieces (and gaining points) come about at large as each of the three opponents likewise do attacks and make threats of capture. Therefore picking friends and enemies has a political quality; ultimately the impromptu teammates will have to combat each other as only one can win. The Cox-Forbes theory of the origin of chess, though debunked, asserts that a four-player version was the earliest form of the game. A description of a four-player chess game is found in an Indian text
Janus Chess checkmate cannot be . Due to the extra pieces, each player starts the game with considerably more " power" compared to standard chess; however, the game has only a slightly higher material "power density", since there is more room for players to maneuver pieces because of the larger board (10×8 = 80 squares). Due to the different board and pieces, players are unable to use normal chess opening theory, and chess tablebases have limited value in the endgame. Janus Chess has been popular in Europe with regular tournaments drawing strong players. Several chess grandmasters have played this game including Viktor