Puzzle Bobble, A.K.A Bust-a-Move, is a puzzle game series created by Taito. It fuses the color matching of games like Columns and Bejeweled with some of the the ball mechanics from Atari's Breakout.
Rounds begin with the top of the screen containing a number of bubbles which must be eliminated in order for the player to win. This elimination is performed by firing a random series of bubbles from the bottom-center of the screen into the existing cluster. Whenever three or more of a kind are touching they pop, potentially causing balls attached beneath them to drop off the screen.
The bubbles, when fired, travel in straight lines and possibly bouncing off the side walls of the arena. they will eventually come to rest either touching one or more of the existing bubbles, or at the top of the arena.
An exponential scoring system is used, leading to large rewards for removing many bubbles at once. As the game proceeds, the top of the playing arena, and all the bubbles, move down the screen after a certain number of bubbles has been fired. The player must remove every bubbles from the arena before any pass a line at the bottom of the arena. Bubbles will fire automatically if the player remains idle.
One or two players can play the game. In the single-player puzzle game, the goal is simply to clear the arena of bubbles. 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 colored bubbles in each arena. When a player removes a large group (four bubbles or more) some of those removed are transferred to the opponent's arena, usually frustrating his efforts at trying to remove all the bubbles from the arena. In some versions, the two player game can also be played by one player against a computer opponent.
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. Some animations of Bub and Bob are based on the original Bubble Bobble arcade game, except Bub and Bob are larger than they were in Bubble Bobble. (Their signs are the same size.) This note only applies to inserting coins in the middle of the game (if a dip switch was set to have "intrude play" enabled), as well as losing a game.