Dots & Boxes against the computer: avoid the third side

Dots & Boxes is the pencil-and-paper classic that many people first played at the back of a school exercise book. You take turns drawing lines between dots, and whoever draws the fourth side of a box claims it. In Games by Zaweba you play against the computer, and the game sits on the Board games shelf.

The rules take a minute to learn. The strategy takes rather longer, which is why it has lasted so well.

Lines, boxes and the extra turn

On your turn, draw a line between two neighbouring dots, either across or up and down. If your line completes the fourth side of a box, that box is yours, and you must draw another line straight away. So one good turn can take several boxes in a row.

When every box has been taken, the player with more boxes wins.

To draw a line, click between two dots. That is the only control you need.

The one rule of thumb

Avoid drawing the third side of a box. If you do, your opponent can draw the fourth side and take it, and then they get another turn. This is the first thing every good player learns, and it shapes the whole early part of the game. While there are safe lines left, lines that do not make a third side anywhere, both players draw them.

Chains and why they matter

Sooner or later the safe lines run out. Then someone has to draw a third side, and the boxes start to fall. Often they fall in chains: a corridor of boxes where taking one opens the next, and the next. A player who is handed a chain can sweep up every box in it.

That is why the game says not to hand your opponent a chain. When you are forced to give something away, give away the smallest thing you can. A single box is far less costly than a long corridor.

Look ahead as the board fills. Count the chains forming and think about which one you will be forced to open. If you can make sure the computer is the one who has to open the long chains, the game is usually yours.

Edges, corridors and the extra line

Draw your safe lines in places that keep options open, rather than in places that start to box in a corridor. Pay attention to the edges, since boxes along the border have fewer sides to share and can turn into chains faster than you expect.

When you take a box, remember that you must draw again. Before you take a run of boxes, think about where your extra line will go. Taking the last box of a chain and then being forced to open a long one is a classic way to lose.

A game for a quick think

Dots & Boxes in Games by Zaweba is short enough for a tea break and deep enough to keep coming back to. Esc pauses the game, F1 explains the rules again, and your wins against the computer are counted on the game's tile in the library. It sits well alongside Noughts & Crosses on the same shelf, another pencil-and-paper game that rewards a little forethought.