西藏夾棋 (Tibetan wedging game) or 青海藏棋 (Qinghai chess) is an abstract strategy game played on a 5x5, 7x7 or 9x9 Alquerque-style board. Players take turns to place their stones on an empty intersection until the board is full except for the center intersection; then they take turns to move a stone to an adjacent empty intersection. When a piece of one color is trapped between two pieces of the opposite color, or between an opposing piece and the edge of the board, that piece changes to the opposite color as in Othello. When one player has no legal move, the player with more pieces on the board wins.