Defender
was developed by Williams Electronics in 1980. It featured 2D,
side-scrolling graphics which were ahead of their time. Set on an alien
planet, the idea of the game was to defeat waves of aliens whilst
protecting astronauts on the planets surface.
The game spawned lots of
clones, including Dropzone which was released by Arena Graphics in 1984
for the Atari 8-bit and Commodore 64 computers. The game won critical
acclaim in most computer magazines of the day, including a gold medal in
Zzap! 64 for the C64
version,with a 95% rating. I remember playing Dropzone on my Atari 800XL
and it was extremely responsive and a joy to play.