Decide which side to command each with their own 12 mission campaign.
The human and alien forces have different infantry, vehicles, facilities and heavy-duty weaponry at their disposal meaning that you'll have to adjust your tactics and playing style to suit the units under your command.
Build, maintain and defend your base from enemy attack. To do this you will have to raise credits by refining oil and then make decisions about where to spend your hard earned credits.
Strategic management of infantry, facilities and vehicles is essential for a successful campaign. This puts you in absolute control of your army and its ultimate destiny.
Aliens are attacking a far-flung human civilisation and are hell-bent on the destruction of the human race. It's up to you whether you want to join the alien hordes as they set out on their mission of annihilation or whether you want to help the humans defend their land and their right to exist!