Commander Keen is the first truly "commercial quality" game to be distributed as shareware. It features ultra-high-speed smooth-scrolling EGA graphics and superb sound effects. The animation and scrolling is updated at nearly 40 frames per second, for comparison, motion picture quality cartoons are filmed at only 24 frames per second.

The story of Commander Keen is epic, and in the style of the memorable matinee serials, like Flash Gordon. You play the role of Billy Blaze, an eight-year-old kid genius who builds an interstellar ship when not working at home on his college fast-track degree. Among other household objects, Billy uses his Nintendo joystick for flight control and his mom's vacuum cleaner (heavily modified) for his ship's ion propulsion system (with pile height adjustment).

At the hint of galactic trouble, Billy dons his brother's football helmet and becomes "Commander Keen" defender of Earth! Ever on the side of justice, fairness, and high-calorie junk food, Keen dispenses justice with an iron hand.

Keen's first adventure takes you to Mars, where the Vorticon invasion force is planning their conquest of Earth. While Keen is exploring Mars the Vorticons steal pieces of his ship and hide them within their cities. Can Keen recover all the pieces and repel the Vorticon invasion? You'll explore many dangerous cities, packed with diabolical traps and hideous creatures, both of Martian and Vorticon origin. Use your pogo stick to reach high ledges and jump deadly pits, and use your ray gun to stun the Vorticon invaders. Can you find the secret city?

Commander Keen: Marooned on Mars created by