C'tan

So here we are, you and me, watching as what was once the Universe crushes itself back into an embryo of indistinguishable matter and energy. We've got our own little bubble of reality to keep us intact, but the math is fuzzy: It's supposed to last forever, the only thing being that the concept of forever was referenced to the spacetime that's steadily collapsing out there. If we've really created our own nano-universe inside of here, will escape make us the god of whatever comes after? Or have we just walled ourselves off, trapped behind a self-built event horizon that a new reality can't permeate? Well, it's nice to be here with you all anyway.
— Rebis
  The C'tan is the closest thing to what mortal tongue can describe the energy beings that exist outside the wall, alongside the Gods of the Forgotten Realms, and the 144 Ars Goetia / Sans Angerium. Their species is are a race of etheric creatures believed to be the first intelligent life in existence. In their true form, they are immense energy creatures able to engulf multiple galactic clusters with their sheer spread, but the largest is that of 'Tiathao' and 'Shi.' which encompass 'half of everything that has, will, and ever be' each respectively. The Rebis claims that they are a fourth generation C'tan, and that not even they know truly the extent of where these creatures came from. (Shi x Tiathao -> Dream x Nightmare -> Ars Goetia / Sans Angerium -> Rebis)   The further down the 'generation' the mother alike to physical life they will be. The highest rank known is generation five, which came in the forms of 'dieties' of alien planets in the far forgotten past.   Rebis instinctively knows two things, that Shi is referred to as 'Ruin Mother' and Tiathao is 'Pale Father'. All C'tan are to refer to them of some variety of these things.   In pre-existence of this current physical galactic cluster, the Rebis claims that the C'tan lived in a unsteady observation with mortal kind, opting to watch them silently as dismissive and blind, idiot, ignorant gods. However, something changed one day. Microbes and radiation mutating the building blocks gave way to a vast spread of creation that was otherwise inconcieveable, and it is from that the C'tan began to mimic their energy readings, similar to how spirits do, to create their own offspring through parts of themselves and sheer will.   These entities, referred to as 'thoughtlings' were more like a cosmic afterbirth of true C'tan, giving way to conciousness and thought for mortal creatures naturally from the amount of energy that was given, eventually mutating off of one another to create flickering motes of conciousnesses.   In places like the Forgotten Realms, Thought Beings, Energy Beings, and Physical beings are one of the many 'examples' of places that existed where these concepts existed on the same plane of being. It NEVER ended well. Physical life and conciousness was seen as a curiosity to the C'tan, something to be toyed with, manipulated, pressed upon, and in some cases broken with a limitless amount of 'tests' were had to decide what to do with them.   The Rebis does not know the full story, but something changed. A truly stable, fully physical world of being was created. Where we are now. To protect it, Pale Father shoved all nonphysical entities from its super cluster, and attached a theoretical placenta to it in the form of the Dreamlands to nourish it. Dream and Nightmare were created by the Pale Father to tend to it. From there, the two entities observed and spread to give birth and conception to the Ars Goetia and Sans Angerium, C'tan who better resembled physical life in their power. But they were still too far away to truly help or understand in the way they needed to.   So; It was through their 'sacrifice' of their energy they created The Rebis, a theoretical which is essentially; a physical C'tan with access still to its energy comprehension.   Pale Father and Ruin Mother; the Rebis claims, are generally more complicated than 'Good and Evil' but none of that matters now. As the Ruin Mother has awoken and seeks to end all of this. The unfortunate realization, the Rebis claims, is that Pale Father likely was not supposed to do any of this, and so they suffer through it under Ruin Mother's slumbering, but now awoken anger.   Something in here, woke up her perception to this place, and for that we all pay the price. "Shi's Throne" it is referred to, though none know exactly what that 'is'. This entity will not cease until all is ended. It will be a endless war, a constant and unbeatable enemy.   But you never thought life was supposed to be easy anyway, did you?