Like the original "Missile Command" and its clones, this game places you in control of Anti-ICBM weapons which you use to destroy an onslaught of missiles (and other nasties) which are dropping onto your nation. The game ends when your cities have all been destroyed. You only gain replacement cities by acheiving certain score thresholds during each attack (level). The main difference between this game and Missile Command is that ICBM3D, as the name suggests, provides a 3D perspective. You take advantage of X-Window's 3-button mouse to control your firing sight ("cross-hair") in 3-dimensions, and change your viewpoint. WWW: http://www.newbreedsoftware.com/icbm3d/