Beyond chess. In this ancient Chinese game, you and your opponent alternately place lens-shaped stones on unoccupied points (intersections) of the board’s grid of horizontal and vertical lines (tournament size, 19 x 19; casual, 13 x 13; beginner, 9 x 9).
One player uses black stones; one white. Black plays first. If your opponent is a rank novice, let him make up to 13 moves before you begin.
The object is to control more of the board than your opponent. You control an area by walling it in with your stones and by capturing any opposing stones inside your walls.
Line-connected, adjacent stones of the same color form a unit. Your unit can be captured when all its liberties (empty points immediately adjacent) are occupied by your opponent. When your unit’s last liberty is occupied, your opponent removes those captured stones. Those empty spaces may then be reoccupied. If you play a stone that captures no opposing stones, hasn’t a liberty, and isn’t part of a unit with a liberty, remove it and any units connected to it (suicide).
To prevent ko (a repetitive situation), you cannot make a play that re-creates a position of all stones on the board that existed earlier in the game. Continue play until you can’t reduce your opponent’s area or expand your own.
Chinese scoring rules: Capture all enemy stones possible. Alternately fill all points that cannot be surrounded by you or your partner. Count 1 point for each intersection you occupy with a stone and 1 point for each empty intersection inside your walls.