This god from the PHB and official sources has been taken nearly verbatim. However, rather than be a god she is instead the greater spirit of death.
The Raven Queen is worshipped by those who stalk the night. Also, like a few of the other spirits, and even some gods, she has her chosen peoples. These are the revenants, brought back from the dead to fulfill her indecipherable and unknowable goals. The Raven Queen is also referred to as the Wings of Death, Sitter of the Black Tower and Skull-Speaker. There are rumors that she dwells in O’pilis Nox’s counterpart in the shadowfell which can only be reached from the top of that accursed tower on certain days.