Three-check chess

Three-check chess, also called simply three-check, is a variant of chess in which a player wins by giving check to the opponent three times. Everything else follows the standard rules of chess, including the starting position and the usual ways a game can end, such as checkmate and stalemate. A move counts as one check whenever the opposing king is threatened, even if several pieces attack the king at once. The game can be played over the board but is especially popular on internet chess servers, where it is a regular variant on sites such as Chess.com and Lichess. Lichess holds a yearly three-check world championship. Its true origin is not known: chess-variant author David Pritchard suspected a Soviet origin and noted that Anatoly Karpov was an invincible three-check player in his youth. Because games are short and often end without checkmate, strong players readily sacrifice material to force a run of checks.