The aliens main strategy, stay in a very small square unless a zombie making machine, or terror machine.( I put the chrysallid in a whole new level past terror) Truthfully the Aliens in UFO-EU/X-Com are not hard at all to beat, keep 3 to 4 spaces between each soilder don't leave a door un opened. Fire all weak psi soldiers so they can't be panicked/controlled. And finally (while I have always never bothered with psi combat, guns are my thing, and screw the blaster gun, too many accidents) make a super psi squad win game)
Anyways back to point.
Civ 5 was a good game, some may prefer the combat of 4 over 5 that is fine.
and Xenonauts has some nice points to market now and show it is different. Chris has so much momentum now he can turn that into moster sales.