There's little in common between StarCraft II and Civilization V, yet a modder on Steam decided to add StarCraft units and lore to Civilization. Finally, we can beat up rival countries with Kerrigan's psionic powers or with Terran siege tanks.
Civilization modders are really into adding stuff from Blizzard games. This one's less ambitious than the awesome Warcraft mod, but hey, there's always room for more. Maybe add the Battlecruiser as a next step? Or an Ultralisk? Or... creep?