>>527373380
sustainer is likely not the primordial one. the sustainer holds humanity and the child(ren) of humanity in utter contempt and calls the twins the means whereby humanity has breached a covenant with god. Judging by the way the sustainer teleports *into* tevyat and the sustainer being the object of skirk's goal, it can be assumed (though this ultimately conjecture and could be misdirection) that they are the figurehead for what is happening outside of tevyat
>>527373469
the twins are representative of the abrogation. if the established lore with khaenriah is anything to go by, this is related to how khaenriah used the abyss to summon/intertwine/trap the souls/essences/etc... of being outside of their universe or outside of the shield set up by the PO in an effort to circumvent the fate of life on tevyat. incidentally, this could be the reason why arle, who wields the crimson moon's semblance (a device probably originally used by the sinners to breach the abyss in the first place) is searching for skirk. in any case, the sustainer is an entity that can fuck with causality, absorb energy, and manipulate the physics of reality. not only do we not know what they can do in particular, but we dont know the implications of the summoning rituals the khaenrians use(d)