Was going through and rewatching the story CS from 2.0 main story, and came across something that made me think. In the post credit roll CS where Bahamut roars, we undergo a migraine/echo vision of a giant dark crystal, which with the following CS with the Ascians, we all assumed that darn crystal was Zodiark. But we see it via the power of the echo, so what if that crystal isn't actually Zodiark, but Hydaelyn losing her light? Perhaps her losing her light turns her into Zodiark? Are Hydaelyn and Zodiark one and the same being, neither existing while the other does, and so must wait for the power of the other to wane?
The scariest part of all this is that the Echo seems to serve as a direct link to Hydaelyn in our minds....if that is Zodiark and we can get visions of it like that, it doesn't bode well for us since that means Zodiark would have a direct link into our minds as well. O.O

*Runs to grab a darksteel hat before its too late.