Quote Originally Posted by PerrinTaveren View Post
yeah that was where i was confused too. since there were final days after they created zodiark in that flashback and people were literally praying for zodiark to stop it and bring back the paradise they had. so i don't get how imprisoning zodiark made a change. it is hinted summoning hydaelyn stopped it maybe? but then again, how is the question. since after she took matter in her hands, world is saved. But we don't know how.
Zodiark did stop the final days by basically creating a shield of aether around the planet so that Meton's dynamis couldn't get through to corrupt creation magic, and from what we can tell, it did work, but the problem became when after half the population sacrificed themselves to summon him, then another half was needed to be sacrificed again to sustain him (so think they were willing to sacrifice 75% of all living people just to protect the world) Venat and her followers thought this was unacceptable and summoned Hydalen to keep Zodiark in check. The aether shield created by Zodiark was still in place on the Source and all its reflections, and he needed to continue to exist in order to maintain it, but in order to stop the human sacrifices, Hydalen sundered and imprisoned him.

She knew it was only a temporary solution, but it was she deemed the right action to save more people from being sacrificed.