If you've played Bubble Trouble then you are familiar with the series. Bubble Struggle was actually the original and is pretty cool. There are 2 objects to the game. The first is to get as many points as possible and the other is to beat the game by reaching and beating level 22. Good luck because it is not easy and Bubble Struggle is very addicting.
[ Arrows: Move | Space Bar: Shoot | P: Pause (only during "Get Ready" screen)]