Defender. Every day of the week.

Defender had much more play variety than the other two.
Both the other two featured single screen played over and over in exactly the same way every time. Defender had you not only killing aliens, but also trying to save people, thus creating a dynamic where you had to do more than just survive, you had to choose when to help, and when to turn tail and run. Oh, and smart bombs to destroy everything. Oh, and the little mini map showing what the aliens you couldnt see on screen were up to was genius.

It was also way harder than the other two, which you'd want if you had one machine for ever more.

Oh, and the sound module was something else. Vastly superior to the other two games.

Interesting fact. The speed increase in Space Invaders that came as you killed more and more aliens (the final few moved like the clappers) was not an intended feature put in by the game designers. It was simple a consequence of the game struggling to render all the sprites when all the aliens were up. As more died, all the computing power went into the last few, and they moved quickly. They intended to "fix" this problem, but play testers loved it so much they thought it was intended and made the game.

Posted By: Under soil heating, Nov 9, 08:46:37