What this game is
Russian draughts is a game about the forced move. Capturing is compulsory, which turns every offered piece into an order: your opponent has to take it, even when taking it wrecks his whole position.
That shapes the play. Games are rarely won by slowly piling up an advantage; far more often a four or five move combination decides everything, one where you give up a piece or two to collect three. And then the second half begins, with kings that fly across the board and capture from any distance.
Rules
- The board is 8×8 and only the dark squares are used. Each side has 12 men on its three nearest rows. You are blue, at the bottom, and you move first.
- A man moves one square diagonally forward.
- A man captures both forwards and backwards: it jumps an adjacent enemy piece and lands on the free square right behind it.
- Capturing is compulsory. If the same piece can capture again after its first jump, the sequence is played to the end. You may choose which of several available captures to play, but the one you start must be finished.
- Captured pieces stay on the board until the sequence is over and may not be jumped a second time. They are all removed at once when the sequence ends.
- A man reaching the far row becomes a king immediately — mid-sequence included — and carries on with the same capture as a king.
- A king moves any distance along a diagonal. It also captures at any distance and may stop on any free square beyond the captured piece — unless the capture can go on from some of those squares, in which case it must stop on one of them.
- You lose when you have no pieces left, or no legal move.
- If both sides play 15 moves in a row with kings only, taking nothing, the game is a draw. A draw is not entered into the score.
How to play better
- Compulsory capture is your weapon, not your problem. Offer a piece so that the forced reply drags an enemy piece to the square where you collect two or three.
- Count every capture to its end. Half of all lost games are a move after which "just one" piece leaves in a chain of four.
- Do not rush to move off your back row. Men on the first rank block the road to promotion, and every one you take away is an invitation.
- Keep your pieces as a connected mass. A man that runs out ahead is usually lost: nothing supports it, and only your opponents are obliged to take it.
- A king is worth not itself but the squares it controls. The long corner-to-corner diagonal is the best place for one.
- Against the computer, remember that it counts material. When you are a piece up, trade: the fewer pieces on the board, the fewer combinations it has left to win the piece back.
A bit of history
Draughts did not grow out of chess but out of a much older game, alquerque, which reached Spain with the Arabs and is documented as far back as the tenth century. Medieval Europe moved it onto a chessboard, and what came out is what we call draughts. The flying king arrived later, following the chess reform of the late fifteenth century that gave the queen and the bishop their long range.
Since then the game has split into dozens of variants, and the differences are fundamental. Russian draughts uses an 8×8 board, a flying king, and men that capture backwards. The international game is played on 10×10 with 20 pieces a side. English draughts, also called checkers, is 8×8 as well, but there a king moves a single square and a man captures forwards only.
It was English draughts that was solved outright in 2007. Jonathan Schaeffer's group at the University of Alberta, who had worked on the Chinook program for nearly two decades, published the proof in Science: with perfect play from both sides the game is a draw. Russian draughts, with its flying king, is orders of magnitude larger and remains unsolved.
This version follows the applet that ran on this site from 2005 and implements the Russian rules in full: crowning in mid-capture, the Turkish strike, the draw after 15 quiet king moves. There is no majority rule here — of several available capture sequences you may take any, as long as you play it out.
About the levels
Easy looks exactly two plies ahead — its move and your reply — and judges the result by material alone: a man is worth a hundred, a king three hundred. It sees neither advancement nor the centre, gives itself no thinking time and answers instantly.
Hard searches with iterative deepening down to six plies, inside about four tenths of a second. On top of material it counts how far a man has advanced towards promotion and adds a small bonus for the sixteen central squares — so it already understands that a man near the crowning row is worth more.
Expert goes as deep as twelve plies and spends around seven tenths of a second per move. Its real advantage is quiescence: a position with a capture still pending is never evaluated, the search is extended until the capture sequence is over. That is why it cannot be caught by a combination beginning just beyond the horizon. It also values king mobility, and in the endgame, once eight pieces or fewer are left, the stronger side stops shuffling and drives its kings straight at the enemy.