From the award-winning creators of Civilization comes an action-strategy game about civilization's last stand. Threatened by an unknown enemy, the Earth's governments unite to form an elite paramilitary organization, known as XCOM, to combat this extraterrestrial attack. As the commander of XCOM, you control the global defense team in a battle against a terrifying alien invasion by creating a fully operational base, researching alien technologies, planning combat missions and controlling soldier movement in battle.Take on a mysterious alien threat and develop a strategy to save your planet with XCOM: Enemy Unknown. Build and expand your XCOM headquarters and lead your squad into deadly and fierce battles against the imminent threat. Recruit soldiers and develop them in order to take them into combat, and uncover and research extraterrestrial technology to enhance and expand your weapons and capabilities. With this Complete Edition, you'll also receive access to the thrilling XCOM: Enemy Within expansion pack, as well as the Elite Soldier, Slingshot and Second Wave add-on content. A new Genetics Lab allows you to physically augment your soldiers' chests, brains, eyes, skin and legs, while a Cybernetics Lab enables the development of the new Mechanized Exoskeletal Cybersuit, or MEC. You now have stronger, faster warriors and a new MEC Trooper class with specialized abilities and suits that can carry flamethrowers and grenade launchers. Your engineering team and the Foundry tirelessly work to develop new weapons and equipment to give your operatives an extra tactical edge against two new alien classes, including the Mechtoid. Fortunately, a valuable new alien resource, the MELD, has been released into the landscape, providing access to new research and upgrades. Then take the battle online to mix and match aliens and soldiers and combine abilities to outsmart and overpower your opponent in adrenaline-pumping, one-on-one, turn-based multiplayer matches. With this Complete Edition, you'll be ready for any alien threat you encounter.