Pieces
20
20
The version of draughts played in tournaments from Amsterdam to Dakar, and a genuinely different game from the eight-by-eight checkers most English speakers grew up with. The board is ten by ten with twenty pieces a side. Ordinary men capture backwards as well as forwards. Kings fly the whole length of a diagonal and take pieces from a distance. And above all, capturing is not merely compulsory — you must take the line that captures the most pieces, even when a smaller capture would suit you better.
You play white at the bottom and move first. Pieces only ever use the dark squares. Tap one of your pieces and the squares it can reach are marked with dots; tap a dot to move there.
Ordinary men step one square diagonally forward when not capturing, but they capture in all four diagonal directions — forward and backward alike. A king moves any distance along a diagonal, and captures by jumping the first enemy piece it meets and landing on any empty square beyond it.
Capturing is compulsory, and among all the capturing lines available you must play one that takes the greatest number of pieces. If that means jumping your favourite piece into danger, so be it. For a multiple jump you tap each landing square in turn rather than only the final one, because two different routes can take different pieces and still finish on the same square.
Captured pieces stay on the board until the whole jump is finished, which means you cannot leap the same piece twice. A man becomes a king only if it stops on the far row; if a jump takes it across that row and onward, it stays a man.
You lose when you have no legal move, either because your pieces are all gone or because every one of them is blocked. Winning adds one to your streak and the computer searches deeper as the streak grows.
The compulsory maximum capture is not a restriction to work around, it is the whole game. Because your opponent has no choice about which line to take, you can hand them a piece knowing exactly where their piece will end up, and set the trap there. Nearly every combination in this game is built the same way: give one, force the reply, take three. Before every move, ask what capture you would be forcing if your opponent took the bait.
Count before you sacrifice. If you give away two men to win back four, you gained two — but only if the line is truly forced. The moment your opponent has a choice of equal-length captures, they will pick the one that suits them, and your calculation collapses. Look specifically for whether two capture lines of the same length exist.
Do not rush to make kings on a full board. A lone king surrounded by twenty enemy men is not the monster it becomes later; it can be trapped against an edge and lost. Kings are worth roughly three men in the endgame and considerably less in the middlegame, which is the reverse of how beginners value them.
Keep your back row for as long as you reasonably can. On a ten-line board the back row is five squares wide, and each one you vacate is a lane through which an enemy man can walk into a crowning. The two squares at the ends of your back row are the ones to hold longest.
Against this computer specifically, the profitable ground is the long forcing sequence. It searches a fixed number of moves ahead and evaluates what it finds, so a combination that pays off just past its horizon is exactly what it cannot see. Combinations of five or more jumps are where a human still beats a modest search.