Ouk Chatrang vs Computer

How to play Ouk Chatrang (Khmer Chess)

Ouk Chatrang is the traditional chess of Cambodia, a close cousin of Thailand’s Makruk and a descendant of the same medieval game that gave the world international chess. It is played on an 8×8 board by two players, each commanding a King (Sdaach), a Queen (Neang), two Bishops (Koul), two Knights (Ses), two Rooks (Tuuk) and a row of Pawns (Trey). The pieces are worth less than their Western counterparts and the battle lines start closer together, so games are sharp, tactical and full of hand-to-hand fighting from the very first moves. This app lets you play a friend on the same screen, or challenge the computer at three difficulty levels and earn ranking points for every win.

The goal

The aim is exactly the same as in chess: trap the enemy King. When a King is attacked it is “in check” and must escape; when it is attacked and cannot escape by any legal move, it is checkmated and its owner loses. If the player to move has no legal move at all but is not in check, the game is a stalemate and ends in a draw. White (the lighter army) always moves first, then the players alternate turns.

The board and starting position

The board is an ordinary 8×8 grid. Each back rank holds, from the corners inward: Tuuk (Rook), Ses (Knight), Koul (Bishop), then the royal pair — Sdaach (King) and Neang (Queen) — and mirrored back out to Koul, Ses and Tuuk. The crucial difference from Western chess is the Pawns: instead of standing on the second rank, the Trey line up on the THIRD rank from each side, one row further forward. That single change puts the armies within striking distance and makes the opening far more direct than in international chess.

The pieces and how they move

• Sdaach (King) — moves one square in any direction, horizontally, vertically or diagonally, just like the King in chess. It may never move onto a square attacked by an enemy piece.
• Neang (Queen, also called Met) — a weak queen: it moves exactly one square diagonally in any of the four diagonal directions. It cannot move straight, so it is far less powerful than a chess queen.
• Koul (Bishop) — moves one square diagonally in any of the four directions, OR one square straight forward. It cannot step straight sideways or backward. This is the same “elephant/silver” move as the Khon in Makruk.
• Ses (Knight) — leaps in an L-shape exactly like the chess knight: two squares one way and one square at a right angle, jumping over anything in between.
• Tuuk (Rook, literally “boat”) — slides any number of empty squares horizontally or vertically, exactly like the chess rook. It is by far the strongest piece on the board.
• Trey (Pawn, literally “fish”) — moves one square straight forward to an empty square, and captures one square diagonally forward. It never moves two squares, even from its starting rank.

Special first moves and promotion

• Sdaach leap: on the King’s very first move — and only while it is NOT in check — the Sdaach may leap once like a Knight to an empty square. It is a one-time privilege, useful for tucking the King into safety early. It cannot be used to escape a check.
• Neang leap: on the Neang’s very first move, it may instead jump two squares straight forward, provided both squares are empty. This lets the otherwise slow Queen reach the centre quickly. After it has moved once, it is a normal one-step diagonal piece.
• Promotion: a Trey promotes to a Neang (Queen) when it reaches the sixth rank — the row where the enemy’s Pawns first stood, three squares ahead of its own start. It does not have to reach the last rank. Promotion is automatic.

Winning, check and draws

You win by checkmating the enemy Sdaach: putting the King in check when it has no legal way to get out. When your King is in check, the status line warns you and the King’s square is highlighted; you must answer the check — by moving the King, blocking the attack, or capturing the attacker — before doing anything else. A game with no legal move and no check is a stalemate, scored as a draw. In the two-player game the Undo button takes back the last move if a finger slips. (Traditional clubs use a “counting” rule to force a result in bare-king endings; this casual version simply calls those positions a draw.)

Relation to Makruk and chess

Ouk Chatrang and Thailand’s Makruk are almost the same game — both keep the short-range Queen, the forward-stepping Bishop, the third-rank Pawns and promotion on the sixth rank. They share an ancestor with chess, xiangqi (Chinese chess) and shogi in the ancient Indian game of chaturanga, which spread across Asia and mutated into each region’s national version. Because the Ouk pieces are short-ranged, the game rewards patient manoeuvring and precise Pawn play rather than the long-range attacks of Western chess. If you know chess, the biggest adjustments are the weak Neang, the Koul that can only creep forward, and Pawns that start one row further up.

Playing the computer (ranked)

In “Ouk Chatrang vs Computer” you pick your colour and one of three difficulty levels. Easy plays loosely and makes deliberate mistakes so beginners can win. Normal looks a couple of moves ahead and punishes obvious blunders. Expert searches deeper, defends its King and rarely misses a tactic. The computer thinks entirely on your device, so it works offline. Beat it to earn ranking points — Easy +10, Normal +30, Expert +100 — and sign in to record your best result on the leaderboard. Draws and losses score nothing, so play the highest level you can actually beat.

Strategy tips

• Fight for the centre with your Pawns early. Because the Trey start on the third rank, the two Pawn walls are already almost touching, so the opening skirmish begins immediately — do not fall behind in the Pawn battle.
• Use the special first moves wisely. The Sdaach leap can whisk your King to a safe corner before the position opens; the Neang leap brings your Queen into play a move faster. Both are gone forever once the piece has moved, so time them well.
• Value your Tuuk (Rooks) above everything else. With the Neang and Koul so short-ranged, the Rooks are the only long-range attackers; open files for them and trade them only for real advantage.
• Push a Trey toward promotion in the endgame. A promoted Neang is not strong, but an extra piece in a bare-piece ending is often enough to build a mating net around the enemy Sdaach.

Frequently asked questions