Bubble Bobble (バブルボブル Baburu Boburu) is an arcade comical action platformer video game by Taito, first released in 1986 and later ported to numerous home computers and game consoles. The game, starring the twin Bubble Dragons Bub and Bob, tasks players with travelling through one hundred stages, blowing and bursting bubbles, jumping on and off blown bubbles to navigate level obstacles, dodging and eliminating enemies, and collecting a variety of items including some that carry 'power ups' and significant bonuses. For example, some wrapped candies allow Bub and Bob to move faster, blow bubbles faster, and blow bubbles at greater distances. Other items, such as umbrellas, allow to skip numerous levels, moving closer to the final level. The game became popular and led to a long series of sequels and spin-offs. The main goal of the game is to rescue Bub and Bob's girlfriends from the Cave of Monsters. It is an early example of an action game with multiple endings, which depend on the player's performance and discovery of secrets.
In the game's plot, "Baron Von Blubba" has kidnapped the brothers Bubby and Bobby's girlfriends and turned the brothers into Bubble Dragons, Bub and Bob. Bub and Bob have to finish 100 levels in the Cave of Monsters in order to rescue them.
In the game, each player controls one of the two dragons. Players can move along platforms, fall to lower ones, and jump to higher ones and over gaps. Each level is limited to a single screen, with no scrolling; however, if a screen has gaps in its bottom edge, players can fall through these and reappear at the top. Each level has a certain number of enemies that must be defeated in order to advance. The players must blow bubbles to trap the enemies, then burst these bubbles by colliding with them. Each enemy defeated in this manner turns into a food item that can be picked up for extra points. Defeating multiple enemies at once awards higher scores and causes more valuable food items to appear. All bubbles will float for a certain length of time before bursting on their own; players can jump on these and ride them to otherwise inaccessible areas. Magic items appear from time to time and grant special abilities and advantages when picked up. Special bubbles occasionally appear that can be burst to attack enemies with fire, water, or lightning. Furthermore, if a player collects letter bubbles to form the word EXTEND, he/she earns a bonus life and both players immediately advance to the next level.
A player loses one life upon touching any free enemies or their projectiles (rocks, fireballs, lasers, bottles). Enemies turn "angry"—turning pink in color and moving faster—if they escape from a bubble after being left too long or the players spend a certain amount of time on the current level. They return to normal if either player loses a life. After a further time limit expires, an additional invincible enemy appears for each player, actively chasing them using only vertical and horizontal movements. These disappear once the level is cleared, or when a player loses a life. When there is only one enemy left, it immediately becomes angry and remains in this state until defeated.
In the 100th and final level, players face a boss. This game was one of the first to feature multiple endings. Completing Level 100 in single-player mode reveals a message stating that the game has not truly ended and a hint to the player: "Come here with your friend." If two players complete the game, they see a "Happy End," in which the brothers are transformed to their human selves and reunited with their girlfriends. This ending also includes a code that, when deciphered, allows the game to be played in the faster and more difficult "Super" mode. If this mode is completed with two players, a second "Happy End" is displayed in which Super Drunk is revealed to be the brothers' parents under the control of some outside influence. The brothers return to normal and are reunited with their parents and girlfriends.