Gomoku

Observe, choose, check

In brief

Complete the line

Complete the line

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Teaching diagram. Coordinates are read from left to right and from top to bottom.

Black has four consecutive stones on D8, E8, F8, and G8. C8 and H8 are empty. Playing H8 creates an unbroken line of five black stones.

Which move wins for Black?

Show the answer

H8 wins immediately. C8 would also win. These two open ends form a double threat.