The player takes the role of a captain on a research mission in outer space. An emergency signal has been intercepted from the planetary system "Apano Sin." Now the player's job is to deactivate the out-of-control defense system of Apano Sin.
To do this, the player takes control of a small space fighter and destroys enemy space craft on top of vertical scrolling backgrounds. The ship can carry up to two different weapons systems. In total there are four different weapons: Green Flash, Blue Blizzard, Bomber and Power Cannon.
After successfully completing the moons of Apano Sin in arbitrary order, the player faces the final level on the planet itself. One unusual feature for a shoot 'em up is that enemy patterns are randomized, so that they can't be learned by heart.