Black plays first. Place stones on intersections of the grid lines.
Stones of the same color connected horizontally/vertically form a group.
A group's liberties are the number of empty adjacent intersections.
When a group has zero liberties, it is captured and removed from the board.
You may not play a stone that would have no liberties (suicide), unless it captures opponent stones.
Ko rule: you may not recreate the immediately previous board position.
Either player may pass. Two consecutive passes end the game.
Scoring (Chinese/area rules): stones on the board + surrounded empty territory.

GO

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