Astral Plane – Where the minds of sleeping mortals travel while dreaming. Also, apparently where Macha is currently.
Home of the Shadows (likely the shadow plane): apparently a pale reflection of Seken. Residents are flat and barely individuals. information is scarce, but they can apparently only gain individuality and grow their personalities by having experiences, which they can’t have at home. Details are still sketchy, but intriguing.
Gai’mas – Tessa, the Priestess of Semias, described Gai’mas as a broken language, which should be in Semias’ domain, but is not because people are still hording bits of it, most notably The Fuzoku Butsu. She stated that the language was used to Name things by the divine, but that mortals spoke it in a reduced sense before the Godswar. She does not know precisely why it ‘broke’, as it was not fully in Semias’ domain.
The Nature of the Divine: According to The Builder (who is admittedly perhaps not the most reliable source), the Divine is restricted by their nature, and is unable to change it. You aren’t exactly clear on what form this restriction takes, but the Builder was adamant that they did not have free will, at least not in the same way that mortals did. His entire attempt at ascension is based on having the power of a God, but the will of a Mortal. This is…theoretically impossible, but he might have found a loop hole? it is all very confusing.