| Differences | 
                  
                    | 
 | 
                  
                    | There is no title screen | 
                  
                    | The score continually counts upwards until it
                        overflows 
 | 
                  
                    | The radar screen is directly under the score
                        instead of under the gauges 
 | 
                  
                    | The radar shows different colored blobs slowly
                        scrolling left to right (red, gray, dark green, orange,
                        black, light green).  Many of these colors are not
                        seen in the final game. 
 | 
                  
                    | Above the radar is what appears to be a larger
                        section of the radar not seen in the final
                        version.  There is a white dot  in the center
                        of this to represent the player. | 
                  
                    | The players ship looks very different | 
                  
                    | The lives counter counts from 0 to 6 ships over
                        and over again | 
                  
                    | The laser heat gauge constantly fills up and
                        then starts over | 
                  
                    | The fuel gauge is functional and will deplete if
                        the player flies around.  Once empty the player
                        will fall and be unable to move. | 
                  
                    | The fuel gauge is blue instead of green | 
                  
                    | The two gauges are in separate boxes instead of
                        being in the same box | 
                  
                    | The blue background around the HUD is missing | 
                  
                    | There are two odd shapes in the center of the
                        HUD where the level counter should be.  The top one
                        is a zig zag shape that constantly moves back and forth
                        and the bottom one is a large close up of your ship that
                        slowly scrolls off the screen. | 
                  
                    | Above the area where the city should be is what
                        appears to be a sunset.  The sky starts out blue
                        and changes from red to orange.  There is a
                        yellowish line under this where the shield is in the
                        final version and the player cannot cross it. | 
                  
                    | The ground and cities do not exist under the
                        shield. | 
                  
                    | The player's movement is very different. 
                        Pressing left and right will change the angle of the
                        ship to one of 8 directions.  Pressing up will
                        start the player moving in the direction (thrust) while
                        pressing down will stop the movement.  If the
                        player is in the air, pressing down will cause them to
                        fall to the ground. | 
                  
                    | If the player flies up into the HUD area they
                        will disappear except for a small flashing dash. |