Dao

1. Each turn, move one of your four pieces in any direction. It slides as far as it can until it hits the edge of the board or another piece.
2. No jumping, no capturing, and no stopping short.

Win by forming a horizontal or vertical line of your 4 pieces, a 2×2 square anywhere, or by occupying all four corners. But beware: trapping an opponent's piece in a corner with three of your own pieces loses you the game. First to 3 wins takes the match.