Graphics by Keith Parks         
     Programming
by Mark Boyns
 
| 
   The object is to
  defend the bases from incoming missiles  | 
  
   Incoming missile
  count increases every level  | 
  
   Shot count
  decreases at level 7, 15, 30, ...  | 
 
| 
   Extra bases awarded
  every 10,000 points  | 
  
   Bonus points
  awarded for remaining bases and shots  |