AI War 2

AI War II is a grand strategy/RTS hybrid against an overwhelming, inhuman enemy who has conquered the galaxy. The enemy has made only a single error: underestimating you. You must steal as much technology as you can, and take enough territory to fortify your bases and launch your attacks.

What Makes the AI Awesome? The AI has a distinct advantage over you in a grand strategic sense, but when it comes to combat and tactics it plays by the same rules as you... and it's very devious.

The core conceit of the AI is that most of the time it's not aware of you. But pieces of its empire become aware of you at various times, and you have to then deal with those pieces in battles ranging from tiny skirmishes to thousands-strong epic encounters.