Sid Meier's Alien Crossfire

This expansion to Alpha Centauri adds 7 new playable factions (2 of them alien and heavily buffed), a few new secret projects, some new alien units, and a few unit abilities. The changes are all really minor. The new factions are fun to play for at least once. Even if one likes the original AC it still makes sense to play this expansion but with the old factions, or even mix the old factions with the new. The new secret project Cloudbase Academy unbalances the end-game too much though since it puts an Airspace Complex into all your bases, and this boosts the growth too much if you have a few Sky Hydroponics Labs and Cloning Vats. So, for fairness sake, you may want to edit **** and make it more expensive to build or remove it altogether (write "Disable" for tech prereq, 4th column). Overall, this expansion takes a great game and adds a bit of extra content to it which is a good thing.