Chess clock Chess clock A chess clock consists of two adjacent clocks with buttons to stop one clock while starting the other, so that the two clocks never run simultaneously. Chess clocks are used in chess and other two-player games where the players move in turn. The purpose is to keep track of the total time each player takes for their own moves, and ensure that neither player overly delays the game. Chess clocks were first used extensively in tournament chess, and are often called game clocks. The first time that game clocks were used in a chess tournament was in the
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