Defcon 5 (1987)

The player takes the role of a DOD operative who must use the BMD(Ballistic Missile Defense System) to protect the United States. This system is composed of ground-based, land-launched, and space-based system components. The goal is to destroy, defeat, confound, or destabilize incoming ballistic missiles.

The game-play is mostly text based with the player entering 5-letter commands or coordinates in order to operate the BMD. In addition to active weapons, the player has access to surveillance system needed to detect missile launches and space mines. These systems are susceptible to visual interference and outages due to their orbits.