It's a hey this thing needs to be stopped because it's on a I hate everything rampage and it doesn't care that those who imprisoned him are long gone. Bahamut also seems to be able to easily enthrall things so if Loiusoix hadn't done what he did I don't know when or where he'd of run out of steam and energy. It also at least through the story of coil explain why the land didn't heal as well as it should have.