Space Infantry: Zero G

Space Infantry: Zero G is a solitaire game of combat in the future set in the world of Space Infantry: the Player will control the soldiers of the human race against the endless enemies lurking in the universe.

The game has been designed to have Zero setup, Zero space required (you only need one A4/Letter sheet) and simple rules, but capable of providing enough challenge and obviously fun. Perfect as a filler or when traveling, the game include nine battles with a progressive complexity (read: challenge), each battle playable in 10 to 20 minutes.

—description from the designer