Quote Originally Posted by Enla View Post
The ones who were sacrificed were willing. The ones meant to be sacrificed to bring them back /were not/. This is what caused Hydaelyn to be summoned in the first place.
oops I did it again..

Hydaelyn herself would have required more sacrifices to be summoned though. From what I gathered Hydaelyn was meant to keep Zodiark himself in check, not the population.