Imagine that aliens are invading the Earth and you’ve been put in charge of the defense of the entire planet. That daunting proposition is at the heart of XCOM Enemy Unknown, the latest strategy game from Firaxis and 2K. Players manage the paramilitary XCOM project, deciding what new projects to research and what new technology to produce so that the XCOM troopers go into battle with the best equipment possible. Do well and the funding nations will pour even more money into the XCOM project. Do poorly and the nations will pull out, leaving the project with even fewer resources to fight back the alien invasion.