After the death of Vordakai, we determined Raven was the lich’s familiar.
He was never found and his status is now unknown.
Unknown creature masquerading as a raven in murders of crows at Varnhold. It could be a druid in wild shape, a familiar or some other polymorphed creature.
Nevertheless it ordered the crows to attack the party immediately and must have known Zalathes was a druid too; therefore, the Raven must be considered an enemy of the party and probably Varnhold.