Bubble Bobble is an arcade game by Taito, first released in 1986. It features two Bubble Dragons, Bub (Japanese "Bubblun"), who is green with yellow spikes/horns and Bob (Japanese "Bobblun"), who is blue with cyan spikes/horns. Together, they journey through the Cave of Monsters to rescue their girlfriends. They move over a system of platforms, busting and pushing bubbles, avoiding enemies and collecting a variety of power-ups.
It was ported soon for numerous home computers and game consoles. The main reasons that many ports of this gameeven when released several years after the originalcan seem lacking and incomplete in some aspects is because the original arcade game, despite its apparent simplicity, features some rather complicated and convoluted game mechanics.
Each level (or round) consists of one screen, with no scrolling or flipping. The dragons can move around the levels by walking on platforms, falling through empty space, jumping through platforms from below and (in some levels) falling through holes at the bottom of the level in order to reappear at the top, or even vice versa (see gameplay techniques below).
Apart from jumping, the characters can blow bubbles. Bubbles also float in from the top or bottom of the screen in many levels. They pop after a certain amount of time, when they hit the dragon's spiked back, if they're squashed against a wall or another dragon or if they're fallen upon. By holding down the jump button, it's possible to bounce on top of bubbles, which is sometimes necessary to reach platforms. The main objective of the game is to trap enemies in bubbles, and burst them, destroying the enemies. Defeating several monsters at once awards exponentially increasing point awards.
Each round also features invisible air currents and custom bubble physics, causing bubbles to move in predetermined trajectories, such as converging to a certain point, moving very quickly or very slowly, being pulled down as if by gravity, etc., usually with notable effects on a level's difficulty.
Some levels have very short bubble-popping times, meaning that bubbles pop almost as soon as they emerge. This becomes extreme in later levels to the point of only being able to kill monsters by "kissing" them (blowing a bubble in such a way that it's immediately squashed against the dragon, causing instant death to an enemy). Time limits are also used to increase the game's difficulty; two rounds having no time limit, some levels are almost impossible to finish under certain conditions (single player, lack of certain bonuses etc.). When the time limit expires, the player does not die instantly, but rather an invincible "Skel" enemy appears for each player, and all enemies become "angry", with a change in color and increase in speed. (Wikipedia)