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Those still stinging from the waste of time which was Slingshot will be happy to know XCOM’s Enemy Within expansion more than makes up for Firaxis’ past failing. As with their Civ V expansions, XCOM’s overall story and direction remain the same with this expansion even while it adds a new dimension to the title.
Playing upon themes brought up in the previous campaign, Enemy Within expands upon the idea of better utilising alien tech for self-enhancement. Along with gene-modded marines, added to your roster now are eight-foot-tall MEC Troopers armed and armoured to the teeth. While the former offer largely passive buffs discovered by dismembering the corpses of aliens, the more tasty additions are the Troopers.