3 Stooges is a 2 player game played on a 6x5 grid of squares, with three cells removed in its of its corners, resulting in a diamond-shaped playing area. Black and white stacking pieces are used; to start the game, the pieces are laid out one to each cell, alternating black and white across the board, but for the long center row of six cells, each of which has two stacked pieces of its color.
On every turn, each player may do one of the following:
Swap the places of any two single, unstacked stones, of either color.
Ko rule - The player cannot swap a stone swapped in the opponent's last move.
Ko rule - After two consecutive swaps, it's illegal to swap again.
Move the upper stone (from a friendly stack of two stones) to an adjacent (orthogonal or diagonal) cell occupied by an isolated friendly stone.
To win, a player must line up three stacks of his own color in a row, orthogonal or diagonal, or stalemate his opponent.