Bubble Bobble, at the time of its release, introduced brand-new play mechanics, with players defeating enemies by trapping them in bubbles they blew, and then popping them.
It was first released in 1986 as a puzzle-action game featuring the two Bubble Dragons, “Bub” and “Bob”. Although the game is beaten by clearing all 100 rounds,
the game contained secret elements such as not being able to get the “true ending” in single-player mode, having hidden commands that led to secret rounds, and containing a ton of different items.
These elements were one of the game’s most important selling points.
Each round even had different air currents that were not visible, so bubbles would rise in unpredictable patterns.
Aspects like forcing players to understand and utilize these different patterns while playing helped make this game a revolutionary action game at the time.