Fight increasingly difficult enemies over 100 levels with the occasional boss fight thrown in as well as bonus stages and a couple of mini games. What at first seems like a classic shoot 'em up with one ship against hordes of alien ships soon turns out to be much more than that. Upgrades for your ship are plenty and even better: the more you play the more upgrades you start with at the beginning of each new game.
Passing level 100 starts you back at the first level with your now upgraded ship blasting through the levels once more. The gameplay is heavily addictive and hard to put down but there is a save feature so you can pick up the game later when you are up again after a needed power-nap.
Weapons range from the single shot you start out with through triple shot, plasma, lasers and more. You can also upgrade your ships speed, number of bullets and how long time other bonuses like shields last. The game has a range of secrets to be unlocked that provide you with huge benefits - some more obvious than others. A profile system keeps track of your progression in the two game modes Mission and Time Trial and hints what bonus you get for playing just another bunch of levels. You know you want to.