Ouk Chatrang

How Ouk Chatrang is played

Ouk Chatrang is the chess of Cambodia. It is Makruk with two differences: the king and the met may each make one special move, and the counting rule starts earlier and ends one move sooner. The goal is to checkmate the opposing king: to attack it so that no move can save it. An attacked king is in check, and no move may leave your own king attacked.

The pieces

The king steps one square in any direction. The rook moves any number of squares along a rank or file, and the knight jumps in an L, two squares one way and one to the side, over whatever stands between. The met, beside the king, steps one square diagonally. The khon, beside the knight, steps one square diagonally in any direction or one square straight forward. Only the knight jumps over other pieces, and a piece captures by moving onto an enemy piece. There is no castling.

Special first moves

On its first move the king may leap like a knight, two files to the side and one rank forward (from d1 to b2 or f2), and the met may go two squares straight forward (from e1 to e3). Both jump over whatever stands between, but only onto an empty square: a leap never captures. The king may not leap while it is in check, and it loses the leap for good once an enemy rook has come onto its file or rank, even with pieces between them. A piece that has moved has lost its leap.

Pawns

Pawns start on the third rank. A pawn moves one square forward and captures one square diagonally forward; there is no double step and no en passant. A pawn that reaches the sixth rank, where the opponent’s pawns started, always becomes a met.

Winning and draws

Checkmate wins. Stalemate is a draw, and so is the same position three times, or a position in which neither side has enough left to mate (a lone met or knight, or a pawn, which can only become a met).

The counting rule

A won ending must be finished in time. Counting starts by itself and is shown in the counting side’s bar. As soon as one side is down to its king and at most two other pieces or pawns, it counts to 63, even with pawns still on the board. When that side has only its king and no pawn is left, it counts from the number of pieces on the board, and the limit depends on what the other side has: 7 with two rooks, 15 with one rook, 21 with two khons, 31 with two knights, 43 with one khon, 63 otherwise. If the count reaches the limit without a mate, the game is drawn.

Where it comes from

Ouk has been played in Cambodia since at least the 12th century, as bas-reliefs on temples show, and like Makruk it descends from the Indian chaturanga. The first nationwide tournament was held in 2008, and in 2023 ouk was one of the traditional sports Cambodia brought to the Southeast Asian Games. This game follows the rules Fairy-Stockfish and pychess play; some players allow the two leaps only until the first capture.

More games

Chess and variants

• Chess · Classic chess or Chess960 with a shuffled back rank, against a bot.
• Chess960 · Fischer random chess: the back rank starts in one of 960 setups.
• Antichess · Losing chess: give away all your pieces, captures are compulsory.
• Atomic chess · Every capture is an explosion that clears the pieces around it.
• Crazyhouse · Captured pieces change sides and can be dropped back onto the board.
• Duck chess · After every move you move the duck, which blocks everyone. No check.
• Fog of War · You only see where your pieces can move. Capture the king to win.
• Friendly Chess · Nothing is captured: pieces unite and set off chain reactions.

The chess family

• Chaturanga · India’s ancient chess, the root of the family: take the king to win.
• Shatranj · The medieval ancestor of chess, with a weak ferz and a jumping alfil.
• Makruk · Thai chess: a slow, strategic game with a counting rule.
• Sittuyin · Burmese chess: set up your pieces, then promote on the diagonals.
• Xiangqi · Chinese chess: a river, palaces and a cannon that jumps to capture.
• Janggi · Korean chess: no river, palace diagonals and a cannon that always jumps.
• Shogi · Japanese chess: captured pieces return to the board on your side.
• Minishogi · Shogi on a 5 × 5 board: six pieces a side, short and sharp games.

More players

• Chaturaji · India’s four-handed chess: kings can be captured, captures score.
• Four Seasons Chess · Alfonso X’s chess for four from 1283: four seasons, the last king wins.
• Three-player chess · Three armies on a hexagonal board: you against two bots.
• Four-player chess · Four armies on a cross-shaped board: in teams or all against all.
• Eight-player chess · Eight armies on a board of 516 squares: all against all, in pairs or four against four.