This submitted theory is a collaboration between Ternasyl and Maoist, both from the Falcom Discord.

A theory relating to to the Septian Church Goddess Aidios, her relationship with septium, pleroma grass and a brief comparison of Gnostic belief and how it relates to Aidios being a prison for the world.

There has been a lot of various theories about the Septian Church’s goddess, Aidios, about her identity, her role in the series. Here’s our take on it.

As we all know, before the first Demiourgos’s suicide, she “created” Pleroma grass as a medium between humans and her. Pleroma grass grows exclusively on septium veins and has a variety of intriguing effects. But we’re not going to ponder about the grass itself, instead, we’re going to look at what it grows on. In Gnosticism, Pleroma is the emanation of the Monad, the true God. It isn’t too far-fetched to assume there’s no higher God in Zemuria than Aidios herself. Therefore, it isn’t too far-fetched to assume Aidios is literally septium veins, or rather, septium itself.

One might argue that the Demiourgos created Pleroma grass, which would discredit the whole theory, but that’s not necessarily true – also in Gnosticism, the Demiourgos is the false, self-proclaimed creator who gives physical form to the already existent spiritual world, created by the Monad, which means that the Mirage Sept-Terrion might have given the physical form of grass to Aidios’ emanations, but hasn’t created them in the first place.

But how is Aidios a prison for anything? We can assume that the seven elements are the fundamentals of the physical, visible world of Kiseki, which makes Aidios the physical world of Zemuria.
Has Zemuria always been like this? Let’s look back at 3rd. Ever since the very beginning of the game, our attention is pointed at a certain quote from the Book of Ezer, which is about the Great Collapse – “That brief hesitation was all it took to spawn a great evil. It crawled through the fields, ran through the hills, and spread disaster in the skies above.”. The game points us to the Great Collapse since the very beginning. That seemingly has no real meaning or purpose, unleast until Kevin and Ries’ trip in Gehenna, where we see statues of someone, presumably Aidios, stabbing themselves. The general take on the statue is that it shows the moment of Aidios’ death, but here we have a slightly different take on it – it shows the moment when she became the physical Zemuria.

Even for a wild speculation crack theory like this, it’s too hard to speculate about the details of the Great Collapse, so we’re leaving that as it is… for now.
Thank you for your attention.