Zap! Your laser fires, but the other starship scoots behind a star back to base for more energy units - then back to battle!
The left player's starship will be positioned above the starbase in the upper left corner of the screen. The right player's starship will be positioned below the starbase in the lower right corner of the screen. The numbers on the bottom of the screen are the player's scores.
Starships can move anywhere on the screen. The object is to deplete your opponent's energy reserve while maintaining your own. Energy is depleted in two ways: by firing your lasers or by getting hit by a laser from the opponent's ship. Each time you fire your lasers you use up 2 energy units. Each time you get hit by the opponent's laser, your ship loses 5 energy units. Flying your starship through EITHER starbase will replenish your energy level back to its original 90 units.
Only 40 energy units can be used for firing lasers. After that, you have to replenish your energy supply before you can fire your lasers again. Having 40 energy units for firing lasers translates to having 20 laser shots. If, however, while firing your lasers your energy level drops to 10 units, you will not be able to fire any more lasers shots, even though you may not have used up your 20 shots. This is a built-in safety device to keep you from accidentally depleting your energy reserves completely thereby obliterating your own starship.
A point is scored each time you obliterate your opponent's starship by running him out of energy units. This is done by depleting his energy reserves before he has a chance to re-energize at a starbase.