NoGo

NoGo is a combinatorial game for two players: Black and White. It is played on the intersections (points) of an initially empty square or rectangular grid (board). Board sizes bigger than 9×9 are not recommended. 6×7 boards have been used in some human matches. NoGo takes the Go concepts of group and liberty and uses them in the most minimalistic possible way. The resulting game, with no captures, no cycles and no scoring, is no rival for Go, but remains a fertile ground for tactical challenges in the Dots and Boxes style. The game was first proposed by John Moore on Sensei's Library on April 1, 2005. Definitions A group is a set of orthogonally connected, like-colored stones. A liberty of a group is an empty point orthogonally adjacent to that group. Play Black plays first, then turns alternate. On your turn, place a stone of your color on an empty point. After your placement, all groups on the board (both friendly and enemy) must have at least one liberty. Otherwise your move is illegal. Whoever makes the last legal move wins.