4 seperate modes to blast through, mix and match from 3 ships and 3 play styles for them. And blast, dodge and hyper your way through 5 levels of bullet madness.
Unless you put it on novice mode then it's seriously easy.
However, the true appeal to this game, as with most of these style of shooters, is the scores, whether you're a perfectionist like me and constantly pushing your own damn score because of tha one bullet that hit you and screwed your hit counter! Or you use score attack mode to se how you compare against others over live leaderboards, that is where the fun comes into it.
Being able to record replays of your runs, and indeed watch those of the people who are able to run the hardest modes with not a single fault is a great feature.
So in much much shorter, If you like scrolling shooters, reflex testing, and constantly striving to beat your score and those of people you've never met, this is sheer quality.
Oh and if you like to dream in a barrage of pink and blue circles also helps.