This game is played on a 9x9 grid. There are 49 balls, 24 and 24 in the color in the players and one special ball placed in the inner 7x7 grid (it can be random, or the players put their balls step by step, or they choose a starting position together). In a step a player can push all the balls in a row or a column to one direction if he/she controls more than half of those balls. The game end if the special ball has 4 neighbors of the same color (that is the winning color).