Are there any entities in the Forgotten Realms that could serve as both Cleric Deity and Warlock Patron?

Death Masks & Tyranny of Dragons

In Forgotten Realms how common are magical means to extend your life?

Does the Raven Queen exist in Faerun, or the Forgotten Realms?

What’s the usual punishment for attempted/successful murder inthe Shining Lands?

Is the Raven Queen part of Forgotten Realms lore?