Age of the Dragons
The cosmology of the universe is one of the few things most religions of the realms agree on, along with the Deities themselves, and is divided into several pieces.
The world exists in a place known as the Astral Sea – also sometimes known as the Ethereal Plane or the Veil. It is a mysterious place where souls can manifest physically, it reaches to worlds and beings beyond not only our knowledge but comprehension.
Within the Astral Sea lies the Heavens, the Hells, and the Materials, along with a host of alien beings. Few mortals dabble with the Astral Sea – usually Mages hungry for the power they think lurks in the Far Realm – the furthest reaches of the Astral Sea. Their descent into madness is often well documented in the journals they keep.
The Materials are three planes that occupy the same ‘layer’ in the Astral Sea. They include the Feywilde – a place of abundant nature where Fae reside, the Shadowfell – the dark and gloomy realm of the dead, and the Prime Material – the physical surface of the planet.
The Prime Material is of course where the bulk of this wiki explains, look to Places for more info.
The Feywilde is a place of mystery and beauty. Few mortals are allowed to venture here, however in areas of abundant nature it sometimes overlaps the Prime Material and a mortal may accidentally wander in. This is where many a story of a missing person in the woods originates.
The Shadowfell is where the souls of the dead end up after traversing the Veil. Here is where they are supposed to be at rest, but since The Fall there has been nothing but unrest. It is a barren landscape pitched in eternal darkness. It overlaps the world of the living in places of pitch darkness and death. Graveyards, deep caverns, and other shadowy places and the night are feared for if one enters the realm of the dead he may not return to the land of the living. The goddess Etra resides here as well. Further complicating the issue, over time the unrest in the Shadowfell has disturbed the souls of the dead. Many have awoken as Undead in the Shadowfell, while others find their way back to the bodies they held in life even without the aid of magic. Among those who rose in the Shadowfell, some of ascended to power – even rivaling the Demons and Celestials that do battle there. These Undead Lords sometimes interfere with the Prime Material as well.
The Heavens are where the Gods reside – with the exception of Etra. Here in their realm they and their agents (the Celestials) make their home in beautiful palaces in lands of exquisite beauty. Unfortunately, few mortals will ever experience the splendor again. After The Fall, the gates were closed. Occasionally a Celestial will heed the call to enter the Prime Material (especially if a denizen of the Hells may be involved), but otherwise nobody leaves or enters the Heavens.
The Hells, on the other hand, are frequently left. Long have the embodiments of Darkness attempted to escape their prison in the Hells – a landscape that may at some points by fiery hot and at others bitter cold, in some places lush with poisonous and carnivorous flora and at others barren. It is not known who imprisoned them here or how it was done, only that they sought every way imaginable to escape. For most of time, only a few had managed to do so. Some learned that mortals can bring them to the Prime Material through certain rituals, while some found other ways that are still a mystery to the rest of them. Then came The Fall.