2012
Go to this link and read this article.
Learn why these items are not threats to the world - or are they?:
Alignment
Polar Shift
Supernova
Volcanoes
Solar Storms
In the movie 2012 there were 2 times that they had to fly their plane fast to escape being destroyed. Play this game and see if you can pilot your way out of harm.
After an alien attack the world is now an unfriendly place. You will have an armored suit and must defend against aliens and robots in Robot Rampage
Another favorite is Bullethead
Or maybe you could be Obama and defend the world against aliens in Obama Alien Defense