Dots and Boxes

Dots and Boxes is the margin game everyone learns at school, played here on a sheet of ruled paper with a red margin and two coloured pens. On your turn you draw one line between two neighbouring dots. Close the fourth side of a box and it is yours: it fills with a scribble in your colour and you get another go straight away, so a good position can run off four or five boxes in a row. When the last line is drawn, whoever holds the most boxes takes the match.

The middle of the game is where it gets interesting. Sooner or later every line you could draw hands something over, and the sheet turns into a set of chains — runs of boxes that all fall at once. The player forced to open the first long chain usually loses it, so the real skill is counting the chains, keeping the count on your side, and giving away the shortest one when you finally have to. The classiest trick of all is refusing two boxes on purpose: leave the last pair of a chain alone and your opponent has to take them and then open the next chain for you.

Pick a 4×4, 5×5, 6×6 or 8×8 grid of dots and play with two players on one phone, tablet or laptop — the turn indicator and the score bar say whose pen is out. On your own, choose Doodler, who cheerfully hands you boxes, Clever, who never gives one away without being forced, or Chain master, who counts the chains and double-deals the last two. Solo games get undo, and a hint will highlight a line that costs you nothing. Your match tally is kept in the browser.