At the top of the rectangular playing arena, a number of balls of various colours are placed in a prearranged pattern at the start of the level. At the bottom of the screen, the player controls the angle of a fixed cannon that fires semi-randomly coloured balls in a straight line. The ball, when fired, travels in straight lines, possibly bouncing off the side walls of the arena, before eventually coming to rest either touching one or more of the balls, or at the top of the arena.
If the ball manages to come into contact with identically coloured-balls, thus forming a group of three or more, those balls, and any balls hanging only from them, are removed from the field of play, and points are awarded depending on how many balls are removed from the screen at once.
An exponential scoring system is used, leading to large rewards for removing many balls at once.
To make life more difficult, as the game proceeds, the top of the playing arena, and all the balls, move down the screen from time to time. This imposes a time limit, as the player must remove every ball from the arena before a ball passes a line at the bottom of the arena.
As well as typically cute Japanese animation (the characters from Bubble Bobble operate the cannon) and music, the game's mechanics and level design were beautifully balanced, and the game was terrifically successful at the arcades, spawning several sequels. It is unusual in being popular with women and girls.
One or two players can play the game. In the single-player puzzle game the goal is simply to clear the arena of balls. The two player game pits two players against each other. Both players have an arena each (both visible on screen) and an identical arrangement of coloured balls in each arena. When a player removes a large group (four balls or more) some of the balls removed percolate over to the opponent's arena, usually frustrating her efforts at trying to remove all the balls from the arena. The two player game can also be played by one player against a computer opponent.
Bust A Move is also