Puzzle Bobble 4
Puzzle Bobble 4 (also known as Bust-a-Move 4 for the North American and European console versions) is the third sequel to the video game "Puzzle Bobble" and is the final appearance of the series on the PlayStation and Dreamcast. Plot. On the planet Bubbleluna lives the twins Bub and Bob. One day, the sun fails to rise because the Fairy of the Night, Cleon, has stolen the light source known as the Rainbow for Full-Moon Madame Luna. She splits this rainbow into 7 light bubbles. Bub and Bob then set off to retrieve these  bubbles and restore the light and peace to their planet. Gameplay. The game features a total of 640 levels. This installment of the series introduces two new features: the pulley system and chain reactions. The pulley system consists of two groups of bubbles attached to either side of a pulley. Popping some on one side will cause that side to be "lighter" and therefore rise. The other side lowers in response. If a pulley is shaking and a bubble is attached, the resulting heavier side will lower. This requires added strategy to prevent one side from moving too far and  therefore losing the game. One possible strategy is to form a bubble cluster between two pulleys to prevent them from lowering or rising at all. Then the player can triangulate until acquiring the necessary bubbles to clear both anchor bubbles, while still keeping both ends of the pulley clustered together. Chain reactions occur only on the two player (or player and CPU) modes. When a bubble is dropped, it can move to another place on the board if this causes more bubbles to pop. If this, in turn, causes more bubbles to drop, then the chain reaction can continue. Reception . Critical reception. In Japan, "Game Machine" listed "Puzzle Bobble 4" on their April 1, 1998 issue as being the eighth most-successful arcade game of the month. Like the second Puzzle Bobble game, "PC Zone" shunned the Windows version for its bad performance on low resolution and older PCs, scoring it 30%. Promotion. The game was showcased at the February 1998 AOU Amusement Expo in Japan.