The question was in Sky Ghost: Army of the Damned, what did the army of the damned refer to?
And the answer was...D, Zombies.
A crazed "reverend" and his minions gather up zombies and tame them with shock collars and such so they can then drop them on neighboring settlements. How do you drop zombies on a place? With big cages that have parachutes to slow them after they're dropped from planes. If a few zombies happen to break their legs on the descent, so what? Plenty more where that came from. It's kind of like a biological weapon.