Your ship can be positioned at any one of six levels in space. Alien craft then approach you from the left and right, and you must destroy them by flipping your craft through 180 degrees and shooting them down.
If you miss the alien craft and they collide with you from the front or the rear, you lose the ship. When you have written off five ships, the game ends.
The graphics are good and so are the sound effects, but the balance of this game seems to be wrong.
There appears to be no difference in skill levels between the six levels in space and therefore, there was little point in moving.
All the alien craft accrue the same points when hit and they all move at the same speed (only the colours and shapes are different).
Also, one's craft has an unlimited supply of ammunition, so there is no penalty for continuous use of the fire button. In addition, there was little difference between the 'slow' and 'fast' speed options.
This game seems to have quite a good potential if the plot and balance of play could be suitably redressed.