Eternals

Overview

Eternals. There are two of them. Only two. And both are enough. But what are we talking about? We are talking about the concepts of Life and Death. Both are the End and the Beginning, the general concept of Life & Death as a personification. So lets meet them.

This is Life. She is the personification of the concept of life. She and Death formed the world, gave it animals and people, from the tiniest microorganism to the Giants and Dragons. She is a kind one since living is hard, dying is easy. She works constantly to get more species to Koria and tries to uphold the lifeforce working inside the continent (and the world). Her protectors and utmost believers (some would say "fanatics") are the Druids who protects the Emerald Planes from destruction or exploitation.
Life has various states of being. This is her Cycle and it shows in the seasons down on Koria. Two of them, Spring and Autumn, you see right here. Her mood depends on the state of her Cycle from cheery in the Spring to broody and energy-depleted in the Winter. Sometimes she is making plans in Winter, but most of the time she looks after the beings in Koria. Every being from the tiniest mouse to the broody Giants gets her attention. She doesn't interfere in matters of life and death like deadly diseases or when someone is about to die for various reasons. That is part of her being. No exceptions, not even for Gods. Which is a different matter, but still.
What she is not doing is creating diseases on her own. That is a thing which developed over time and makes the whole experiment more fascinating. Sometimes she whispers ideas and hints into the ears of other gods like Luseus or in the ears of healers if a disease is too dangerous or lethal.
Her workplace is stationed high above the world in an orbit where she has every material there is at hand and a worktable.
She is deeply in love with Death and even more after both discovered that he has a Cycle as well.

Eternal Life (Spring) by CrazyEddie via Midjourney

Eternal Life (Autumn) by CrazyEddie via Midjourney

Eternal Death by CrazyEddie via Midjourney

This is Death. He is the personification of the concept of Death. He and Life created every species in Koria, from the smallest microorganism to the brooding Giants. He is a kind Death because he knows that living is hard and dying is easy. For every species he created an afterlife. Every afterlife is held in a blind-glass-book-like shape and stored in shelves throughout the palace of Death.
Together with Life he created the species throughout Koria. Just as his other half Life Death is worshipped by a lot of people like some humans or the High and Silver Elves.
Just like Life he also has a Cycle where he needs to find an apprentice who is going to succeed him. In his case it is more like a year-long training for the future Death with a ritual at its end to become the new Death. In his palace he has a refuge which is part of the inner temple structure (a temple inside a palace) and houses a huge obsidian stone. This is his resting place or when he wants to look at more specific things. For that purpose the obisidan stone is there with its myriads of facets. What is he seeing there? Who knows...
He is deeply in love with Life since the days of the Creation.

Overview

Both Eternals are personalisations of the entire concepts. They do not know that and they do not know that they are called "Eternals". They are just Life & Death. They are deeply in love and have a private space in the Caretaker's Inn to discuss matters of Life and Death. Without Life there is no Death and without Death Life has no meaning.

Palace of Death by CrazyEddie via Midjourney

Workbench of Life by CrazyEddie via Midjourney