Monochromatic chess d2 and f2, the white king can move from e1 only with castling and then g1–h2–g3–... so the pawn on g3 cannot be white. In Bichromatic chess, the opposite restrictions apply. A piece on a white square must move to a black square and vice versa. Hence pawns cannot capture (or advance two squares) and bishops cannot move. Also, castling and "en passant" are impossible, and queens behave like rooks. Monochromatic chess Monochromatic chess is a chess variant with unknown origin. The initial board position and all rules are the same as in regular chess, except that pieces that begin
Three-player chess have three cells obliquely adjacent, and three cells adjacent at points. Circular boards have three- or four-sided cells, but not triangular or quadrilateral. Some variants incorporate fairy chess pieces in addition to standard chess pieces. The introduction of a third player drastically alters the style of play, even when standard pieces are used. Many chess openings are useless due to the extended board and third player. Each player must think twice as far ahead—anticipating the moves of both opponents, with the added complexity that the next player may move to attack either opponent. If a player trades off pieces with