BTW I missed discussing the Aliens in Beyond Earth. My encounters with them were limited to the early game. They're like Barbarians but there are a handful of types. Flying melee dudes, ground melee dudes, artillery dudes and the siege worm which is very tough to kill. They spawn from Alien Nests that need to be destroyed otherwise they'll keep spawning. By the end game there's no sign of any of them. They are a pest, especially to growing outposts but I feel they're just barbarians with a different coat of paint. They may react differently if you go down say the Harmony affinity route but for Supremacy it's a simple matter of exterminating them so they dont bother you anymore.