[Spoilers] The general crackpot and head-canon thread

[Berethos]

Leaving void-crazy Nabriales aside, Lahabrea's big expodump in the Praetorium seems to indicate that the planet can continue to exist just fine without Hydaelyn, which wouldn't be possible if she were, or was crucial to, the upkeep of the planet itself. It's also not a distinction he would have any reason to make if ending the planet itself was his objective.

My pondering wasn't really about the her being crucial to the upkeep of the planet, but rather whether or not the existence of aether is tied to her existence. I think it's us mortals who are responsible for the upkeep of the planet, using or abusing aether as we do.

Still, cutscene #11 in the Unending Journey, right? The part where he calls her a "parasite that must be burned out if the planet is to recover"? He does believe the planet can continue just fine without Hydaelyn, but in the sense that they need Zodiark instead. Interestingly, he also talks about imbalance and that if "it is permitted to worsen, the very laws of existence - both aetheric and physical - will be warped beyond all recognition" and goes on to claim that Hydaelyn is the source of that imbalance (hence his belief that she needs to be replaced with his own god, and an early echo of what Hydaelyn tells us, that Zodiark was the cause of the imbalance and that she excised him).

That being said, I think that expodump just indicates that Lahabrea believes the planet can exist just fine without Hydaelyn, and since part of that belief is Zodiark replacing her (in fact he says Zodiark's return is necessary to excise her completely) I don't think what he's saying quite reaches the level of indicating that the planet's existence (aether included) is independent of either being.

The scene really only goes so far as to say he believes she needs to be replaced and leaves the question of whether either one is necessary wide open and unanswered.

Also possible that it's among the things Lahabrea is wrong about, according to Elidibus' comment, and Lahabrea's knowledge of what is and isn't necessary for the future of either the planet or the deities could be quite lacking.

Basically I'm not inclined to believe Lahabrea as a source of Word of God information, not at the present time anyway.