Pop the bubbles by shooting your bubble at clusters of two or more bubbles that have the same color. When a match is made, you get an ever-increasing number of points as each bubble pops. Any bubbles, regardless of color, that are hanging off the group you destroyed will also pop. This will earn you even more points per bubble. You can increase your score by including a bonus multiplier in the match. The multiplier is applied to the entire score from that match, including all hanging bubbles that were removed. However, multipliers that are not inside one of the matched bubbles don't count. At intervals, the bubbles drop down one row as the ceiling descends. When a bubble reaches the bottom, the game ends. With each passing level, the ceiling drops more quickly. There is a fixed starting position in each of the first 20 levels, and thereafter you begin with three random rows of bubbles. For really big scores, try to combine multipliers, which are multiplied together. Also, try to build large hanging groups that you later destroy. But don't get too greedy, or you won't get through the level!
