The last line takes it.
Draw a line between two dots. Close a square and it is yours — and you go again. The trick is knowing when not to.
Closing a square gives you another turn, so a run of squares all falls to one player. Late in the game the board becomes a set of chains, and whoever is forced to open one loses all of it — which is why giving two squares back can be the winning move.
You
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Computer
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