Marseillais chess Marseillais chess Marseillais chess (also called Double-Move chess) is a chess variant in which each player moves twice per turn. The rules of the game were first published in Marseillais local newspaper "Le Soleil" in 1925. The variant became quite popular in the late 1930s with such chess grandmasters as Alexander Alekhine, Richard Réti, Eugene Znosko-Borovsky, and André Chéron playing it. A player can either move one piece twice or move two different pieces on his turn. Castling is considered a single move. When a player gives check on the first move, he loses the second move of his turn.
Null-move heuristic null-move heuristic in zugzwang positions, most chess-playing programs that use the null-move heuristic put restrictions on its use. Such restrictions often include not using the null-move heuristic if Another heuristic for dealing with the zugzwang problem is Omid David and Nathan Netanyahu's verified null-move pruning. In verified null-move pruning, whenever the shallow null-move search indicates a fail-high, instead of cutting off the search from the current node, the search is continued with reduced depth. Null-move heuristic In computer chess programs, the null-move heuristic is a heuristic technique used to enhance the speed of the alpha-beta pruning algorithm. Alpha-beta pruning speeds