If anyone has read my fan fiction (see signature), I felt like it'd be a real proper ending to go outside established lore and just have fun making up a situation. In it, my main character, Sola, essentially merges with a powerful Daedra, Xinryk (made up) who has dreams of becoming a Daedric Prince and eventually overthrowing the whole of the Daedra and Divines. Well, Sola and Xinryk merge after Sola uses some particularly strong Daedric magic, and then Xinryk becomes part of Sola. This comes complete with a small realm in Oblivion that she inherits from Xinryk (the realm is also named Xinryk), Daedric servants, and of course imortality and stuff like that. So, that's all the background information that's vital.

This actually isn't all that weird in the grand scheme of things. Let's not forget about the quest where we see a mortal become a god known as the Wilderking/queen.

Just go along with me

In Latin, Magnus means great, and Sol means Sun, so Sola would be Sun (feminine version). So the name would essentially mean Great Sun where there's a denotation that it's feminine. Furthermore, Magnus is also one of the gods in Elder Scrolls, particularly the one who helped create Nirn and magic (oversimplified), so there's an intentional overlap in that aspect too. This also reflects back onto Xinryk's grand plan of 'replacing Magnus'.

Sola is a light enough of a character in terms of morality. She's a good enough person in morals, but her choice in magic is often apocryphal. It's important to note that in game and in my writings she is a Templar. She is able to learn Daedric magic though, so she really contrasts with the light and dark in her choice of magic. Going on, her relatively 'light' self combines with the dark, evil Xinryk, which further puts forward the idea of duality in her nature.

This should, of course, bring back an idea of Azura, who is the Daedric Prince of the Dawn and Dusk. This is intentional. You see, Sola used to worship Azura, so naturally, some of her choices in knowledge would be based on her choices of worship. She also worshiped Meridia, which helped to influence her choice to become a Templar. I would like to bring to light that Magna-Sola is not in a position to challenge any power from Azura (or is she? A supposed topic of debate among scholars).

Fitting with her choices in game, Sola is a mage. Of course, in game I can't load her up with every single spell because of class restraints, but in my head and in writing she's a strong mage who's built herself from her ability to learn very easily. She learns magic because she likes the pursuit of knowledge. This drives her to learn all that she can from all magical schools and backgrounds. She learns all types of Destruction, Restoration, and Templaric magics (so all in game, Templaric meaning the 3 Templar skill lines), but further augments her abilities with Daedric, dark, and vampiric (she's not a vampire though, just uses their magic) magic.

So quite literally she's a walking spellbook who uses all types of magic.

While Sola is a good clothier, armor maker, and woodworker, she makes no attempts to further her crafts towards a special artifact. She does have some of her crafts stocked up, but they are not necessarily special artifacts.

Sola much prefers to take advantage of artifacts that have real power.

This all being said, her family tries to hunt down what remains of her possessions when she disappears from Nirn. This includes her writings and weapons and remaining clothes, but they are of no magical significance. Purely material.

Well, as I've mentioned, Magna-Sola inherits her realm from Xinryk. It is very much the same. I wrote Xinryk in as a reject from Mehrunes Dagon, so the small realm he pulls from him is very similar.

Notably, it looks very much like the Deadlands (to get a good idea of what that looks like, go do a run of City of Ash II), has a Daedra population that were originally Xinryk's followers.

Most important is the Tower, the aptly named Tower of Xinryk, and then later the Tower of Magna-Sola following her ascension. It is the cultural and magical center of the realm, including the history of the realm itself.

In terms of population, while specific numbers are unsure, the realm is populated with both Dremora and lesser Daedra. Clannfears include part of the population. But perhaps more impressive are the intelligent Dremora, which have a few designations, including Seducers.

In terms of special inhabitants, there is but one:
Warden-General Vyrkyl was a Dremora prison warden from Coldharbour who served Magna-Sola as a loyal-enough companion in her mortal years, and was freed from service from Molag Bal by the powerful magics of Magna-Sola, who he then willingly joined with. He is the general of Magna-Sola's Daedric forces.

A common name for Magna-Sola is The Celestial Lady, although it should be specifically noted that she is presumed to be distinct from the constellation.

Magna-Sola has no descendents of her own, and but she had a sister, who had children. In the 4th Era, people who can trace lineage to her sister are restricted to only a few people in Cloudrest in Summerset, and a notable Imperial family: the Luxen family, which is particularly known for magical ability.

In mortal life, Magna-Sola was an Altmer.

Magna-Sola existed as a star in the sky from her ascension during the 3 Banners War until its disappearance following the invasion of the Summerset Isles by Tiber Septim.

In the Cloudrest area of Alinor, her area of origin, she has a small following who worship her as a local god.

Speculation exists that she came into contact with Talos (Tiber Septim), and that the two may have had a power struggle during his conquests, although it is clear that if that happened, the winner was Talos.

Debate exists whether or not Magna-Sola has the power of a powerful Daedra, or a true Daedric Prince/Divine. She may or may not have come into contact with the Amulet of Kings, which may have granted her power. But due to a lack of information, it cannot be decided.

A researcher for the Empire, in the 4th Era, published a work that compiled the information he could find on Magna-Sola. The obscurity of the topic landed little popularity among scholars.