Transcendental Chess of one side can be any of 4²×6!÷2² = 2880. There is no castling. On the first turn a player, instead of making a move, can transpose any of two pieces on the back row. In Chess960 the back rows are mirror images, but in Transcendental Chess the setup of black and white is different 2879 out of every 2880 times (there being a 1–in–2880 chance that both sides will draw the same setup). This can create inequalities in the position. One way to equalize these inequalities is to play a couplet: the players play two games, one each as
Fifty-move rule Fifty-move rule The fifty-move rule in chess states that a player can claim a draw if no has been made and no pawn has been moved in the last fifty moves (for this purpose a "move" consists of a player completing their turn followed by the opponent completing their turn). The purpose of this rule is to prevent a player with no chance of winning from obstinately continuing to play indefinitely , or seeking to win by tiring the opponent. All of the basic checkmates can be accomplished in well under 50 moves. However, in the 20th century it was