Bubble Bobble Revolution
Note: This game is also titled Bubble Bobble DS.
At the title screen in the Classic version, press L, R, L, R, L, R, Right, Select. Touch the door that now appears in level 20 to start the bonus rounds.
At the title screen in the Classic version, press Select, R, L, Left, Right, R, Select, Right.
Defeat the Classic version Boss using two players. Then, press Left, R, Left, Select, Left, L, Left, Select at the title screen in the Classic version.
Enter "I.F" as your initials at the high score screen. If you entered the code correctly, you will hear a sound. A Coke may now appear on floor 1. When collected, it will trigger a meteor shower to kill your enemies.
Collect nine letters throughout the game. You must kill at least four enemies with a single Super Bubble, then collect the key that they drop. After defeating the Boss of that group of levels, it will drop a letter instead of the big gem. You must collect a letter from every Boss in the game (nine total) to unlock the final ten levels.
Successfully complete all 100 New version levels to unlock Robolun.
Successfully complete all 100 New version levels with Robolun to unlock Lovelun.
In the Classic version, there is no apparent continuation mode. However, when you get a "Game Over", go back to the screen where you start on level 1 and scroll down. You will see the Bubble Bobble dinosaur go down on a elevator-type platform to stop at the last level you were at. For example, if you died at level 14 then you can continue again at that point after the "Game Over".