- Trackball: Use the trackball to direct the crosshair gunsight around the screen; the speed at which it moves is determined by how fast you can roll it.
- Firing Button: Use this button to make the cannon nearest to your crosshair's position fire a shot; they may have up to 12 shots on screen at a time.
- Shield Button: Use this button to make all four of the cannons temporarily activate their shields; the shields shall kill everything which flies into them.
- 1 or 2 Player Buttons: Push these buttons to begin a 1 or 2 player game.
These corner-mounted lasers are the protagonists for this game; their mission is to destroy the flashing red missile bases upon the revolving planets (which look impressive for 1982), while at the same time destroying the missiles they (and any Satellites, Saucers, and Fireballs that may appear) fire at them, because if they cannot their doom will be sealed. Once they've destroyed all the red missile bases upon the planet between them they will fly towards the planet and you shall receive a bonus of the level's number multiplied by how many cannons you have remaining (but it stops at 8) - and you shall also receive a bonus cannon at every 20000 points by default. Also, at the start of the game and after every third level the cannons will be flying through hyperspace as a squadron of Scouts come flying towards them in an attempt to collide with them; pushing the Shield Button will also have no effect while in hyperspace, which means you will have to kill the Scouts quickly before they have a chance to ram the cannons.