Chakra (chess variant) in "100 Other Games to Play on a Chessboard" (1983, 2002) by Stephen Addison. Chakra is played on a standard chessboard and has many of the standard play conventions as in chess, including check and the winning objective, checkmate. Stalemate, as in chess, is a draw. The king in Chakra is named "emperor". Each player starts with 16 pieces: 1 emperor, 1 empress, 1 samurai, 1 monk, 2 monkeys, 2 courtesans, 2 chakras, 6 swords. The emperor, empress, and monkey perform identically to their chess counterparts (king, queen, and knight, respectively). The others are governed by special fairy rules. There
Chess and is provably less than 10, with a game-tree complexity of approximately 10. The game-tree complexity of chess was first calculated by Claude Shannon as 10, a number known as the Shannon number. Typically an average position has thirty to forty possible moves, but there may be as few as zero (in the case of checkmate or stalemate) or (in a constructed position) as many as 218. Chess has inspired many combinatorial puzzles, such as the knight's tour and the eight queens puzzle. The idea of creating a chess-playing machine dates to the 18th century; around 1769, the chess-playing automaton