Checkersinternational draughts, 10×10

Goal of the game

Leave your opponent without a move: capture all their pieces, or put them in a position where they cannot play. Either way, they have lost.

Play only takes place on the fifty dark squares of the board.

Setting up

• A board of 100 squares; only the 50 dark squares are used.
• Twenty men per side, on the first four rows at each end.
• White moves first.

Moving

• A man moves one square diagonally, always forwards, onto a free square.
• A man never moves backwards… except to capture. It is the rule that throws players coming from English checkers the most.
• A king moves along a whole diagonal, as many squares as it likes, like a bishop in chess.

Capturing

• Capturing is mandatory. If a capture exists, you are not allowed to play anything else.
• A man captures by jumping over an adjacent opposing piece onto the free square right behind it — forwards or backwards.
• Captures chain: if after the jump the same piece can capture again, it must. That is a multiple capture.
• A king captures at a distance: it slides along a diagonal, jumps an isolated opposing piece and lands on any free square behind it.
• Captured pieces are only removed from the board at the end of the sequence. So you can never jump the same piece twice.

The majority rule

• When several captures are possible, you must choose the one that takes the largest number of pieces.
• A king does not outrank a man: what counts is the number, not the quality. A capture of three men comes before a capture of two kings.
• When the numbers are equal, you choose freely.
• This rule is what gives international draughts its depth: you force your opponent to capture where you want by offering them the longest sequence.

Crowning

• A man that reaches the opponent’s back row and stops there becomes a king.
• If it only passes through that row during a multiple capture, it is not crowned and carries on capturing as an ordinary man.
• A newly crowned king cannot move on the same turn: its power only applies from the next move.

Endgame and draws

• You lose when you have no pieces left, or can no longer make any legal move.
• The game is drawn when neither side can make progress, especially in endgames with few pieces.
• Three kings against one king: the stronger side must win within sixteen moves, otherwise it is a draw.
• Two kings against one king, or one king against one king: draw.

The mistakes that cost the most

• Forgetting that men capture backwards. An advanced piece is never safe.
• Pushing a lone piece ahead. A man out in front with no support is an offering.
• Capturing without counting. Before each capture, check the reply: the mandatory capture is your opponent’s favourite weapon.
• Neglecting your back row. Emptying it opens the way to your opponent’s crowning, and a king is worth several men.

Controls

Keyboard and mouse

• Click a piece to see its legal moves, click the destination square to play.
• When a capture is mandatory, only the pieces concerned can be selected.
• In a multiple capture, each jump is played one after the other; the path stays on screen.

Touch screen

• Tap the piece then its destination. Playable squares are marked.
• The majority rule is applied automatically: moves that capture too few are refused.
• A count of remaining pieces is shown on each side of the board.

Frequently asked questions

What is the difference between international draughts and English checkers?

The board (10 × 10 against 8 × 8), the number of pieces (20 against 12), men capturing backwards, the long-range king, and the mandatory majority capture. They are two clearly different games.

Can a man capture backwards?

Yes, in international draughts. It can only move forwards, but it captures in all four diagonal directions.

Do you have to capture the most pieces possible?

Yes. When several captures are possible, the rules require you to take the one that captures the most pieces, with no distinction between men and kings.

Does a man that passes through the back row become a king?

No, only if it stops there. A man that crosses it in the middle of a multiple capture stays a man and carries on capturing.

How does a game with no winner end?

In a draw, when neither side can make progress. Counting rules limit endgames with few pieces, for example sixteen moves to win with three kings against one.

More classics, free as well

• Minesweeper — the grid, the flags, the timer
• Dominoes — twenty-eight tiles, the line to extend
• FreeCell — eight columns, four free cells, almost always winnable