Bubble Bobble

BUBBLE BOBBLE's release in 1986 introduced the two bubble dragons, Bub and Bob, and brand new play mechanics, with players defeating enemies by trapping them in bubbles and then popping them. Although the puzzle-action game can be beaten by clearing all 100 rounds, it also contains secret elements such as not being able to get the "true ending" in single-player mode; hidden commands that lead to secret rounds; and a ton of different items. These elements are some of the game's most memorable and important features. Each round even has different air currents that are not visible, so bubbles rise in unpredictable patterns. Aspects like forcing players to understand and utilize these different patterns while playing help make this a revolutionary game that is fun to play anytime.   From: www.nintendo.com