In the year 2097, mankind is invaded by an alien race and it is up to cyborg soldiers controlled by the player to destroy the invasion force.Fight your way through seven increasingly difficult levels,defend the boss at the end of each level.Since forward movement is not automatic, the game imposes a time limit in the form of an energy bar that slowly drains as time goes on. If the bar empties completely, you lose a life. It is refilled when you pick up "E" icons or complete a level. The energy bar does not represent health, as touching one enemy or bullet will immediately cost you one life. After dying, you reappear at an earlier point in the level.