Notes

4-player chess
4-player chess (also known by various brand names) can be an adaptation of chess to 4 players. It is played on a board that is 8-by-8 but with a 3-by-8 extension on each side, so it looks like a cross.

Rules

Pieces are put as in a normal chessboard at each player's first row in the extensions. The king and queen placement varies. Pawns progress and attack diagonally forward only. You're allowed to use en passant. Castling is performed the same way as in normal chess. Pawns may promote upon reaching any player's first row. A new player may only respond to check on his/her own turn. Similarly, a checkmate is only validated on that player's turn. A stalemate is when the player whose transform it is cannot move. A checkmated player leaves the game, but his/her pieces stick to the board (although they can not move). The last player standing wins. In a variant, the king is captured like any other piece instead of checkmated, and the capturing player gets to utilize the captured player's pieces. Additional rules tend to be added to prevent teaming with other players. https://worldseniors2014.org may also be played. Players at opposite sides of the board are teammates, and cannot capture each other's pieces, and a king is only considered in balance if an opponent piece can is attacking it. The overall game has ended when both players of one of the teams are eliminated.

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