What is Grand Chess?
Grand Chess is chess on a 10×10 board with two extra pieces for each side: the archbishop, which moves as a bishop or as a knight (letter A), and the chancellor, which moves as a rook or as a knight (letter C).
The rooks stand alone in the corners of the first rank. Every other piece starts one rank higher, on the second rank: knight, bishop, queen, king, chancellor, archbishop, bishop, knight from the b-file to the i-file, leaving a2 and j2 empty in front of the rooks. Ten pawns fill the third rank, and Black mirrors White.
There is no castling. Pawns may step two squares on their first move and can be taken en passant. Promotion is the big change: a pawn that reaches its 8th or 9th rank may promote or stay a pawn, and on the 10th rank it must promote. It may only become a kind of piece its side has fewer of than at the start: a queen once your queen is gone, a rook once you have lost one, and so on. With nothing lost, a pawn cannot move onto the last rank, though it still attacks the squares there and can give check.
Checkmate wins, and stalemate, threefold repetition, the fifty-move rule and insufficient material draw as in standard chess. You can play Grand Chess online, against the computer, or with two people on one device. It doesn't combine with Chess960, Three-Check or material odds.
Rule changes
| Rule | Standard Chess | Grand Chess |
|---|---|---|
| Board | Standard Chess8×8 squares. | Grand Chess10×10 squares, files a to j and ranks 1 to 10. |
| Pieces | Standard ChessKing, queen, two rooks, two bishops, two knights and eight pawns. | Grand ChessThe same plus an archbishop, which moves as a bishop or as a knight (letter A), a chancellor, which moves as a rook or as a knight (letter C), and two more pawns. |
| Starting position | Standard ChessThe pieces on the first rank and the pawns on the second. | Grand ChessRooks in the corners of the first rank; knight, bishop, queen, king, chancellor, archbishop, bishop, knight on b2 to i2; ten pawns on the third rank. |
| Pawns | Standard ChessMay move two squares from the second rank and can be taken en passant. | Grand ChessMay move two squares from the third rank and can be taken en passant. |
| Castling | Standard ChessAllowed once per game on either side. | Grand ChessNot allowed. |
| Promotion | Standard ChessCompulsory on the last rank, to a queen, rook, bishop or knight of your choice. | Grand ChessOptional on the 8th and 9th ranks and compulsory on the 10th, and only to a kind of piece your side has fewer of than at the start. If there is none, a pawn cannot move onto the 10th rank. |
| How to win | Standard ChessCheckmate the opponent's king. | Grand ChessThe same: checkmate. Stalemate, threefold repetition, the fifty-move rule and insufficient material draw as in standard chess. |
History
Grand Chess was invented in 1984 by the Dutch game designer Christian Freeling. He called the two new pieces the marshal (rook and knight) and the cardinal (bishop and knight); here they go by the neutral names chancellor and archbishop.
It belongs to a long family of chess games that add these two compound pieces, which goes back to Pietro Carrera's 10×8 game of 1617 and includes José Raúl Capablanca's game of the 1920s. Its own touches are the square 10×10 board, the rooks alone on an otherwise empty first rank, where they can slide across from the first move, and the promotion rule, which means no side can ever have more of a kind of piece than it started with.