This is one of the classic titles I spent a lot of time on, with a lot of interesting features (terrain deformation, unit customization, government customization ...) added on to your typical 4X game. That makes it one of the older games I still go back & play from time to time, and now I don't have to go get my CD. The only thing preventing me from giving a 5 star review was Alien Crossfire, the expansion not being available. Signing on today, I saw that not only is Alien Crossfire available, but they added it to the original at no extra cost.