Zariel
From Oberon_wiki
Zariel is the name given to the ruler of the First Plane of Hell - Avernus.
It is said that Zariel once once a Celestial (specifically a Solar) who betrayed her "people" and fled to Avernus to escape their retribution. Once in Avernus she quickly rose through the ranks of the Fiends that dwell there and became their ruler.
On Oberon she is worshipped by "the Cult of the One".
