The Archs are not understood to be sentient creatures per se, but rather the physical and sentient embodiment of another planar dimension within Binral. What this essentially means is that by planar theory, Estel and Behesael—or the Archexist and Archdemon respectively—don’t exist by themselves, but give life to the existence of another planar dimension while physically manifested in the Binral Dimension, thus allowing these dimensions to be perceived in Aloria. Or so the Seraph implied, their true nature is unknown and untested. These creatures, due to their limitless tapped energy from other planar dimensions, have immeasurable powers of destruction or salvation, and have been the key subjects of all major events on Aloria for the past seven thousand years at least. Primarily, from what little reliable sources can be accounted, the Archs are concerned with undoing their unnatural existence by destroying the tether between dimensions, and this is where the theory of that concept gets more convoluted. Scholars believe that the only reason the Archs exist in Aloria is because they are known to exist. If no living creature retained any memory of the existence of these Archs, or the dimensions they represent, they are assumed to simply just vanish. This would explain why Void Invasions have occurred, but why they generally avoid non-sentient or self aware creatures and purely target intelligent life. It would also explain why the Archs (or more specifically the Arch Demon) always fails and comes back, as the thorough destruction of life on Aloria is incredibly difficult, even for an omnipotent being who is partially constrained by the laws of existence of the Binral dimension. It was always believed by the Elves that their Arch, Estel, was both their goddess and a creature of good will. Recent events in the global catastrophe of the Bone Horror Crisis however have created the implication that Estel was never morally righteous by free will, and once her constraints were broken, she unleashed hellfire on Aloria. These events shook the foundations and core tenets of the Faith of Estel, but at the same time motivated larger cross-species efforts to research ways to re-restrain the Arch, and to extend that ability onto the Archdemon wherever he may reside.
Note: The Archs are purely progression beings and are not playable.