The Bureau: XCOM Declassified - Survive, Adapt, Win

We now face an opponent from beyond our world, and they have technology decades beyond what we possess -- we must make it our own. Their weapons will become our weapons, and when they do, we shall annihilate them. You now have new orders -- survive, adapt, win.
We are at war, and not the one we were expecting. Our combined military forces have been routed. The comms have gone dark. The red phone will not be ringing.