Divayth Fyr is a 4,000+ year old Telvanni Arch-Sorceror who was so powerful that even Daedric Princes gave him a wide berth. He was easily by far the most powerful spellcaster in all of eastern Tamriel (If not all of Tamriel). Only a select few beings such as Liches, Vampire Ancients or the Tribunal are older than him. Divayth Fyr was on the same power level as Mannimarco before he became the God of Worms (Revenant Moon). Like said before, Divayth Fyr was well known for trafficking with the Daedric Princes, and doing so on even terms. He helped author several books upon the subject of Daedra, and is one of the few spellcaster's who know how to open portals directly into the Oblivion realms. He's one of the only mortals to ever visit Apocrypha and return. Divayth Fyr was so ingenious, that he was able to create a potion that could purge the negative effects (Deformity, Insanity) from a divine curse/gift (Corprus), while retaining the benefits (Agelessness, immunity to Diseases). Divayth Fyr was also the caretaker and friend of the last known living Dwemer, Yagrum Bagarn, tonal architect to Artificer-Lord Kagrenac.
Divayth Fyr could've went "Kamehameha" all over Ancano's ass even when he controlled the Eye of Magnus. Divayth Fyr could make the Thalmor shake in their boots and piss their pants. The list could go on and on, but to put it simply, he was a pure Bad Ass Mother [censored].
He's basically the Elminster of Morrowind.
Except Divayth Fyr isn't hopped up on divine steroids. Once Mystra died and Elminster lost the Chosen powers she had bestowed upon him, he was still a powerful Mage, but not the most powerful one by far. Larloch, Szass Tam, Telamont Tanthul, Rivalen Tanthul, or any other number of Archmages could've kicked his ass up and down Faerun then. Especially considering how Elminster was finally killed by Manshoon, a middle ranking Mage. All of the power that Divayth Fyr has, he's earned himself.
Aside from Divayth and speaking of "living gods" does anyone think Vivec will return?
Vivec was taken by the Daedra, Azura specifically. She held a trial to hold him accountable for the crime of breaking his oath to her and Nerevar. Vivec had several mortals acquire the reagents (which he said was evidence) he'd need for a ritual, and in performing this ritual, he somehow used CHIM to banish Azura from Mundus. I don't believe Vivec actually attained true CHIM, considering he wouldn't of needed the reagents for the ritual if he had achieved true CHIM.