Bubble Bobble

Bubble Bobble is an arcade game by Taito, first released in 1986. It was ported soon for numerous home computers and game consoles. The game features two cute 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.

Game mechanics
The original arcade game, despite its 1986 release date and its apparent simplicity, features some rather complicated and convoluted game mechanics, one of the main reasons that many computer or game console ports of the game, even when released several years after the original, can seem lacking and incomplete in some aspects.

Levels
Each level (or round) consists of exactly 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, then burst the bubble, thus destroying the enemy.

Each round also features invisible air currents and custom bubble physics, causing all bubbles to move in predetermined trajectories like converging to a certain point, moving very quickly or very slowly, rising too fast, 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 is extreme to the point of only being able to kill monsters by "kissing" them in later levels - which means blowing a bubble in such a way that it's immediately squashed against the dragon causing instant death to an enemy. Very short time limits are also used to make the game more difficult, with two rounds having no time limits and a few of them being almost impossible to finish under certain conditions (single player, lack of certain bonuses etc.). It's important to note that when you run out of time, you do not instantly die, but rather an invincible "Skel" enemy appears (two if there are two dragons playing) - for more information on the Skel enemy, see below.

Scoring

 * Bursting a bubble : 10 points.
 * Killing one monster : 1 000 points.
 * Killing two monsters at once : 2 000 points.
 * Killing three monsters at once : 4 000 points.
 * Points double for each extra monster killed at any one time.
 * Normal Fruit : 700 points.
 * Bonus Score Items (popcorn, burger etc) : 500 to 4 000 points.

Enemies
There are a variety of enemies that move about in different patterns. Contact with an enemy (or the missiles fired by some) will kill a dragon. The dragons' job is to complete the level by killing all enemies in it. If this is not achieved within a time limit, the message "Hurry up!" will flash across the screen. When this happens, enemies become "angry" (making them red and move faster thus making them more dangerous). Approximately ten seconds later, one or two Skel enemies appear on screen. Enemies also become "angry" if they escape from a bubble that is not burst quickly enough by one of the dragons. They calm down when one of the dragons die (although probably only when the Skels (see below) appear and your character touches an angry enemy at that time). When in Super Mode, enemies get swapped with a counterpart, e.g. Hullaballoons replace Monstas and viceversa.

There are 7 kinds of normal enemies, plus the final boss and two kinds of invincible monsters that appear after the "Hurry up!" limit, each with their own names. Roughly, in order of appearance, they are:
 * [[Image:Benzo.gif]] Bubble Buster (Japanese "Zen-Chan"): A box-shaped, clockwork walking monster with a medium moving speed and good jumping abilities. Interestingly, this monster appears in the graphic tiles of the ROM of the arcade game Chack'n Pop, along with the Stoner and Beluga, but doesn't actually appear inside the game. Super Mode counterpart: Incendo.
 * Stoner (Japanese "Mighta"): A walking monster with red eyes wearing a white robe, much like a ghost. Has a medium moving speed, good jumping abilities and able to shoot. This monster actually first appeared in Taito's 1983 game Chack'n Pop. Super Mode counterpart: Drunk.
 * [[Image:Blubba.gif]] Beluga (Japanese "Monsta"): A flying blue/dark purple monster shaped roughly like a small whale. It flies fast but can only bounce off walls to change direction. This monster also first appeared in Chack'n Pop. Super Mode counterpart: Hullaballoon.
 * [[Image:Boaboa.gif]] Hullaballoon (Japanese "Pulpul"): A pink flying monster looking like a toy bear with a small rotor on his head. Flies around slowly but with greater control than the Beluga, and creep in very small openings that other monsters and players cannot pass through, thus making it very dangerous in some rounds. Super Mode counterpart: Beluga.
 * [[Image:Incendo.gif]] Incendo (Japanese "Hidegons", singular): A fast walking monster with shooting abilities, but poor jumping. Unlike the Stoner, he doesn't have to stop walking in order to shoot fireballs. Super Mode counterpart: Bubble Buster.
 * [[Image:Mushroom.gif]] Coiley (Japanese "Banebou"): A mushroom shaped-monster which can only move by making short jumps, having a single powerful spring instead of legs. Super Mode counterpart: stays the same.
 * [[Image:Drunk.gif]] Willy Whistle (Japanese "Drunk"): A fast moving monster with good jumping capabilities, and able to throw a bottle which rebounds off walls and is re-caught by the thrower. The final boss is modelled after them, but is instead called Grumple Gromit or Super Drunk. Super Mode counterpart: Stoner.
 * [[Image:Invader.gif]] Super Socket (Japanese "Invader"): A robotic-looking monster, fast, but can only move left or right, and downwards if it reaches the end of a platform. It can shoot something resembling lightning, but only vertically (downwards), making it very dangerous in some stages. First appears on stage 60, and doesn't appear at all in the Super version of the game, being replaced by Incendo or Coiley instead.
 * Baron von Blubba (Japanese "Skel-Monsta"): It is the invincible monster that appears after the time limit for a round has expired (this limit can be as low as 1 or 2 seconds on some rounds, but there are two rounds with no time limit; round 94 and round 100). It looks like a white Monsta but it can only move vertically or horizontally at timed intervals, but can pass through walls, ceilings, floors and it speeds up each time players avoid getting caught, down to the point of moving continuously. In two players mode, two Skels appear, each one homing on one player only, although both players can be killed by touching either of the Skels. A Skel can only be destroyed by killing a player, or if a player who has just been killed touches his companion's Skel while he is still flickering, and thus invincible. However, he disappears when the last regular enemy is destroyed. Another way to get rid of Skel is to pick up the flashing heart powerup (the only one which remains on the screen after the "Hurry up!" warning.
 * [[Image:Rascol.gif]] A smaller Skel Rubblen (Japanese "Rascal") also appears in the secret diamond-filled rounds, which can be accessed by special bonuses that appear on rounds 20, 30 and 40 under certain conditions (explained in later section). Losing one's last life inside such a secret room will cause the maximum round reached to be "Round 102", "Round 103" or "Round 104" depending upon in which secret room death occurred, and the first new game started after that will teleport players to the first secret round straight from round 1, but will also cause secret rounds to appear earlier, at stages 10, 20 and 30, and the special 20-stage skip bonus on stage 40 instead of stage 50.
 * [[Image:Boss.gif]] Grumple Gromit (Japanese "Super Drunk") is the endgame boss that appears in level 100. He is huge, bounces off walls, and fires arcs of bottle-shaped missiles. The level contains a magic potion that lets you breathe lightning bubbles, and you have to hit him with lots of lightning to trap him in a bubble. If this bubble is not popped soon enough, he will escape and become angry just like regular enemies.

Weapons and bonuses
The dragons' main weapon is their ability to blow bubbles. After being blown, they shoot forward for a short distance, then float upwards slowly. It is possible to jump on bubbles to reach otherwise inaccessible areas. An enemy hit by a forward-shooting (not floating) bubble will be trapped in it. The bubble can then be popped, killing the enemy and turning it into an item that can be collected for bonus points. If left floating, it will become angry and escape the bubble after a while.

In some levels, there are special bubbles that appear by themselves:
 * Bubbles with letters that yield an extra life and the ability to skip the current level when one collects a complete set - all six letters spell 'EXTEND'. Extend bubbles appear when one has popped several enemies at the same time. They will only appear on levels which have holes in the top or bottom of the screen.
 * Water-filled bubbles that can be popped to release a stream of water that flows down and drowns enemies, turning them into 7000-point blue diamonds.
 * Bubbles containing lightning bolts that, when the bubble is popped, shoot sideways (even through walls) and kill any enemies they hit, turning them into 8000-point yellow diamonds. The lightning goes in the opposite of the direction that the dragon that popped it was facing.
 * Bubbles containing flames that, when the bubble is popped, drop downwards setting any surface they touch on fire for a short time, killing any monsters that touch the flame and turning them into 9000-point red diamonds.
 * A very rare red bubble with a pulsating yellow spark, which when popped awards 100,000 points and gives the player which popped it the ability to breathe fireballs for the six consecutive rounds. This bubble appears randomly with a 1/4096 chance.

Power-ups include:
 * Red Shoes that enable faster walking and jumping.
 * A blue bubblegum which increases the travelling and forming speed of bubbles.
 * A purple bubblegum which increases the shooting range of bubbles.
 * A yellow bubblegum that increases the rate at which bubbles can be blown.
 * A yellow lamp which gives all three bubble-related bonuses.
 * A red cross which gives the player who takes it the ability to breathe flames until the end of the current round.
 * A yellow cross which causes several lighting bolts to cross the screen, killing any monster they hit, including bubbled ones.
 * A blue cross which kills all monsters by flooding the round with water. This takes some 3 or 4 seconds to complete though, and players are still vulnerable.
 * A red lamp which instantly kills all monsters, turning them into 9000-point red diamonds.
 * A purple bomb, which instantly kills all monsters, turning them into 10,000-point dark blue diamonds. You can't blow any bubbles after the explosion.
 * A red trophy, gives you all the basic power-ups.
 * A purple trophy, a smart bomb that kills all enemies and turns them into diamonds.
 * A blue trophy, gives you extra points when you run along the ground.
 * A blue umbrella, advance three rooms.
 * A yellow umbrella, advance five rooms.
 * A purple umbrella, advance seven rooms.
 * A diamond necklace, releases a ball that flies around the screen and turns enemies into diamonds.
 * A red ring, gives you 100 points for every bubble blown.
 * A silver ring, creates a stream of stars that kill all enemies.
 * A blue ring, gets you points while running around.
 * A purple ring, gives you 500 points every time you jump.
 * A book, smart bomb that kills all enemies and turns them into diamonds - "Throw the book at them!"
 * A glowing heart, enemies freeze and you can run into them.
 * A candy cane that gives large bonus fruits at the end of the round that are 10000 to 30000 points depending on the color of the candy cane.
 * A treasure chest, similar to candy canes except diamonds fall.
 * A clock/watch, stops level timer and changes screen color.
 * A bell, activates alarm that will warn the player that a secret weapon is about to appear.
 * A skull, turns the enemies fast and nasty.
 * A potion, fills the screen with various items, collect all of these for a 100,000 point bonus

Secret rooms
If a player can survive until stage 20, 30 and 40 without losing a life, a door icon appears that, if collected in time, transports Bub and/or Bob to one of three secret rooms. Along with 36 diamonds, there is a coded message written on a plaque at the bottom of each room. The first line of this indicates the alphabet ( = A,  = B etc. ) and the text that follows is a cryptic message explaining various game tips, although those "tips" are relatively obvious and poorly-translated.

Transliterating the messages, they read as (spelling and grammar as they appear in the game):


 * First Secret room (with a Grumple Gromit statue (with his eyes struck out)): "If you want to become the old figure, use the power of your friendship, and fight with me!".
 * Explanation: The message essentially tells the players that they have to reach Grumple Grommit to become human. Also, the tone of the message suggests that the messages are written by Grumple Gromit himself.


 * Second Secret room (with a big broken Lightning bottle): "I enclose these magical medicine here, because those are my worst fears....".
 * Explanation: Grumple Gromit explains his weakness to thunderbolts, which is indeed the weapon that players must use against him; the final level provides the Lightning bottle, which enables the players to breathe lightning bubbles.


 * Third Secret room (with a heart under a glass pane): "If you want to get back your love of truth you must help each other until the last....".
 * Explanation: Perhaps the most cryptic of the three messages, this refers to the fact that the game cannot be completed unless both players reach the final round and destroy Grumple Gromit together.

This coded alphabet is used to display the "Super Mode" code (after finishing the game with two players in 'standard' mode), and appears in several other Taito games, like Rainbow Islands and the Puzzle Bobble series.

Secret doors appear on levels 20, 30 and 40, with one that skips you forward 20 levels if you make it to stage 50 without dying. 

Secret rooms trivia

 * Dying inside of a secret room is possible, if killed by the secret's room time up monster, called Rascal. If that happens, the player will lose a life and if that was the player's last life, the game will end by causing the maximum reached round to be "Round 102" for the first secret room, and "Round 103", "Round 104" for the second and third, accordingly.
 * Performing the previous actions will also trigger a glitch in the first new game started, by causing the player to be transported automatically from round 1 to the first (or second, or third, depending on where the last life was lost in the previous game) secret room. This will also disrupt the order in which secret rounds appear, by making them appear earlier.
 * In the second secret room, the thunderbolts actually seek out the players themselves, and by parking a player to the far right side of the round, will cause the thunderbolts to start striking on the far left side and eventually re-emerging from the right side.

Bonuses and events
A relatively unknown and obscure part of Bubble Bobble gameplay has always been the way the various bonuses appear. While most of them may appear completely random, the game actually keeps a series of internal (and unseen) counters about events such as number of jumps, jumps over bubbles, bubble bursts, bubbles blown etc. during a round or in the whole game, maximum number of monsters blown in a certain round etc. and these events are actually used to determine which bonuses will appear, and to a certain extent when they will appear.

Some known events and the effect they have on bonuses are:

The number of distinct EXTEND bubbles that will appear on a round depend on the maximum number of monsters killed during the round, or on a previous round if said previous round didn't have "openings" for EXTEND bubbles to fly in, or was completed before they could appear. In general, killing N+1 monsters will make N distinct EXTEND bubbles appear. Since the game actually can have only 7 monsters per round, killing 7 monsters in a single bubble cluster will make all 6 EXTEND letters appear.

In Taito's PC port, however, killing N monsters will cause the N-th letter of the word to appear - making the N extremely hard to get because there's only few levels where you can easily pop five enemies simultaneously. This is probably a bug.

Another known event-triggered event is the appearance of candy cane bonuses: if a player rides a bubble more than 20 times, then a candy cane will surely appear in that round.

Other bonuses can be made to appear in similar manners, and there is at least one internet page listing some of the events and their effects.

For a special bonus on the NES version, a player must enter the password HIJID, select 2 player continue, and finish round FO (last level) with both players alive. After the entire ending has run and the player is prompted to press start, the player will receive a reward. The reward is a sound test for the whole game.

Playing techniques and styles
Bubble Bobble is a game heavily relying on gameplay and precise technique rather than graphics, and it features a series of special techniques and tricks a player can perform to maximize his or her score, make some rounds of the game easier or faster to finish or just to be able to survive or even finish a round.

Some of these techniques have special nicknames, which may differ from player to player and from country to country.


 * Kissing monsters or just kissing means killing a monster by blowing a bubble at almost contact distance: the monster will be instantly bubbled and the bubble will be instantly popped, giving the visual effect of the player killing a monster with a "kiss". Some players flip their joysticks in the opposite direction after pressing the bubble buttons, giving more chances of an "instant pop" and changing flight direction for the dead monster. This technique is useful in stages where monsters move too fast, bubbles last for too short a time or it's otherwise hard to bubble them normally. Of course good timing is required for this technique to work.
 * Riding bubbles means keeping the jump button pressed when dropping on a bubble: if done correctly, instead of popping the bubble, your dragon will instead jump on it, possibly continuously, enabling him to "ride" bubbles in order to reach otherwise unreachable areas. Some stages can't be finished without this technique.
 * Climbing is a step up from riding bubbles. It means standing at half a bubble distance from a wall, jumping and blowing a bubble almost simultanously, jumping up from that bubble and blowing another bubble and so on. This is necessary if the air current pushes down bubbles but you need to climb up. Having the rapid-bubbling power-up (the yellow candy) makes climbing a lot easier, especially if you got the running shoes already.
 * Bubbling oneself through means "riding a bubble" through the opening at the top of a stage or even just through the ceiling of a stage in order to appear at the lower part, like some flying monsters can do. This technique is required to finish some stages or to get unstuck from some places, or just to save time.
 * Blowing against the wall means blowing bubbles against wall at contact distance: the bubbles will pop immediately thus giving the player 10 points per bubble pop. This can be used to either increase a player's score, or to set a player's score to a specific amount, in order to do other tricks.
 * Two equal digits means using the "blowing against the wall" technique or other score-adjusting techniques in order to make the two penultimate (100s and 10s places) digits of at least one player equal, e.g., 456770, before the last enemy bubble is burst. If done correctly and the score is not modified when this occurs, then all remaining non-special bubbles on screen will be turned to 700-point bonuses, whose appearance depends on the digit picked. E.g., 7 gives Chocolate Ice Creams, 3 gives Hamburgers, and so on.
 * This trick is easier to do with two players (one player adjusts his score and the other bursts the bubbles), but it can also be done with only one player, although calculating exactly how much (and if) one's score will be modified when bursting the last enemy bubbles can be extremely complex, if not unpredictable, especially if there are very large and clustered bubble bunches.
 * Rounds with numbers ending with 5 and 0 up to and including level 50 generate bonuses from bubbles automatically, though, and some rounds (including round 1) do it by default.

Moon Water storyline
On the original Game Boy version of Bubble Bobble, and Classic Bubble Bobble for the Game Boy Color, there is a storyline in which only Bub is involved in the gameplay.

In this uncommon storyline, Bob (as a human) has an unknown sickness, so Bub has to pass through the hundred levels to defeat Super Drunk and get the Moon Water. There is no mention of the "Cave of Monsters" in this version.

In Classic Bubble Bobble for the Game Boy Color, Bob (as a bubble dragon) has the unknown sickness. Bub has to go through a number of levels (lesser than the arcade or Game Boy, etc versions) and defeat the Darkness Drunk in order to gain the Moon Water. Again, there is no mention of a "Cave of Monsters".

Ports
The popularity of Bubble Bobble led Taito (or its licensees) to port to many home computers and video game consoles. Ports of the game were released for the Commodore 64, ZX Spectrum, Commodore Amiga, Atari ST, MSX, Amstrad CPC, X68000, PC (MS-DOS, 1989 and 1996), Apple II, Sega Master System, Game Boy, Game Boy Color, Game Boy Advance, Nintendo DS, PlayStation, Sega Saturn, Nintendo Entertainment System, Famicom Disk System, Sega Game Gear, mobile phone (Sprint PCS), and UltraCade's Taito Arcade Classics. An version also exists for the BBC Micro on public domain though never officially released.

In October 2005, a version was released for the Xbox, PlayStation 2, and PC as part of the Taito Legends compilation of classic arcade games.

Game mechanics in conversions and ports
Bubble Bobble has been widely regarded as one of the most playable games of all time, owing much of its success to its previously described game mechanics, which are only apparently simple, and its many hidden features and secrets. Also, most Bubble Bobble players usually manage to master techniques such as riding bubbles, 'bubbling' oneself through the screen or 'kissing' monsters, and expect them to work all the time.

Some Bubble Bobble ports however, from the date of release of the arcade version up today, have been heavily criticized for their mechanics deviating significantly from the arcade version, adversely affecting the gameplay.

For example, in many versions of the game the two-digit trick to make extra bonuses appear at the end of the stage just doesn't work, or the score and bonus awarding system is entirely different, in part due to the complexity of the original one, and most of the aforementioned techniques can be much harder or impossible to reproduce, thus completely changing (arguably ruining) the gaming experience.

Examples include even comparatively recent versions such as the (1996) PC/PlayStation/Sega Saturn versions by Acclaim: they either have different game mechanics (too fast dropping speed, barely working shoes, bubbles going through walls, different jumping physics and many non-implemented techniques) or different behaviour for some monsters (especially the time-up monster).

Another example is the early 1989 PC version by Novalogic, which had the possibility of diagonal jumps with a single keystroke (thus enabling players to go through walls), lacked completely the ability of kissing monsters, and had different rules governing the appearance of some bonuses (most notably the orange-yellow sweet).

The various Nintendo NES and Game Boy ports and sequels are very different, often featuring scrolling screens, different enemies, and the ability for the dragons to fly.

In general, there are as many variations to the game mechanics as there are versions, with some being more faithful to the arcade version than others and some resulting in noticeably different gameplay experience. Although that is a general rule regarding ports of any game, in Bubble Bobble it can become very noticeable and annoying because of the game relying primarily on its fast paced and trick-filled gameplay.

One of the few versions having game mechanics and gameplay very close to the arcade is the Sega Master System version, despite its introduction of extra gameplay elements. Moreover, the version included in Taito Legends for the Xbox, PS2, and PC should be a near-perfect copy of the original arcade version, as it supposedly features the original ROM running under emulation.

Legacy
Bubble Bobble inspired many sequels, including:
 * Rainbow Islands - The Story of Bubble Bobble 2 (1987)
 * Rainbow Islands Extra Version (1988)
 * Final Bubble Bobble (1988 Sega Master System)
 * Parasol Stars (1991 originally released for NEC PC-Engine, converted for Amiga, Atari ST, Game Boy and Nintendo Entertainment System (Europe))
 * Bubble Bobble Part 2 (1993 Nintendo Famicom, Nintendo Entertainment System, Game Boy)
 * Bubble Bobble II (World) / Bubble Symphony (Europe, Japan, U.S.) (1994 Arcade, Sega Saturn (Japan only))
 * Bubble Memories - The Story of Bubble Bobble III (1995 Arcade)
 * Rainbow Islands - Putty's Party (2000 Bandai Wonderswan)

There are a couple of previous Taito games which sort of anticipated the Bubble Bobble legacy because of their inclusion of characteristic common elements or even monsters (e.g. the Mighta and Monsta both appeared first in the game Chack'n Pop, and in fact level 29 of Bubble Bobble is a direct copy of level 1 of Chack'n Pop) :
 * Chack'n Pop (1983)
 * Fairyland Story (1985)

Bub and Bob also appeared in Puzzle Bobble, otherwise known as Bust a Move in the United States. Bust a Move was followed by many sequels, for many consoles, including PlayStation, Nintendo 64, Game Boy, Game Boy Color, Game Boy Advance, Nintendo GameCube, PlayStation 2, Xbox and even the N-Gage, along with computer and arcade versions. This spin-off franchise became more popular than Bubble Bobble itself, and has (so far) outlived it.

Similar games, spinoffs, and clones
Bubble Bobble's successful gameplay has inspired not only many official sequels and spinoffs by Taito, but also a number of games with very similar gameplay elements. The most important of them include:
 * The non-scrolling platformer action.
 * Dividing the game into many levels (typically above 30).
 * Defeating enemies by trapping them somehow instead of killing them right away.
 * Collecting bonuses and finding secret ways of increasing their value.
 * Collecting letters to gain an extra life.

Some examples of successful non-Taito video games resembling Bubble Bobble in some or even all of the above aspects are:
 * Rodland by Jaleco (1989).
 * Snow Brothers and its sequels by Toaplan (1991).
 * Tumblepop and Diet Go Go by Data East.



Clones
Ultra Balloon (1996), by SunA Corporation (also manufacturer of Hard Head series), is an evident Bubble Memories copy and the only Bubble Bobble-inspired arcade game to actually copy the bubble-blowing and popping system.

Bubble Bobble also inspired a few software publishers to publish derivatives of the game for the PC and Mac. Such titles include Bubble Bobble World, Bubble Bobble Quest, Bubble Bobble Nostalgie, Bub & Bob, and The Bub's Brothers. Such games are marketed online.

Trivia

 * This was one of the first games to feature multiple endings.
 * In 1996, Taito announced that they lost the original source code program to Bubble Bobble following a reorganisation - when it came to the recent ports and sequels, they had to work from program disassembly, playing the game and (mainly) the various home computer ports.
 * The game forbids the initials 'SEX' on the high score table. If you try, it gets changed it to 'H.!'. In Japan, the letter H is occasionally used as a slang term for perverts. (See ecchi.)
 * Tom Gault holds the official record for this game with a maximum possible 5 823 600 points on March 4, 1988.