This is probably one of the best machine coded games ever written for a home micro. Kevin Baker, who wrote Jawz, Tobor, 3d Star Wars and many other popular games, considers D-Fenders one of his best games.
The game is all action with any type of alien attacks, including skydivers with a flying saucer. Sometimes you look ahead, the echo sounder shows a full screen full of enemy attack. The only way out is to use Baker's bomb, this perfect weapon erases everything in its path. But you only have three Baker bombs for your life's mission, so use them sparingly.
The rest of the time you use your thermal lasers and depend on maneuvering your spaceship to keep you and your crew alive. With straight pull and reverse fiber, this fantastic machine code based game can go on for hours.