Fourty levels of non-stop classic retro arcade action! The game has an arcing storyline where you start out mining in an asteroid field, discover the alien attack, make a fighting retreat back towards Earth only to have it destroyed out from under you. From there you must seek to avenge your destroyed planet on the alien scum! Press CTRL or Z to fire primary weapon. Press X to fire secondary weapon. Press Space to Jump or switch Turrets. Use the right, left, up, and down keys to move around.