The game works in stages where the goal of each stage is to reduce the number of blocks on the board to three or less. You can move the one block removed from the rectangle around its perimeter using the wheel, and you can click to push it into the board, causing one block to pop out of the opposite end. To remove blocks from the board, you must arrange a horizontal or vertical line that stretches the entire length or width of the rectangle such that all blocks in that line are the same. A timer is on the right side of the board, which resets when you make a match as previously described, but if the timer fills, more blocks are added to the board (but if you need to add more blocks, you can press the space bar at any time). Should the board get so full of blocks that you would no longer have enough space to move the extra block around the perimeter of the rectangle, you lose.

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