The Silent Crows

Hook

Three crows repeatedly followed and watched the party as they crossed Rivalis.

The same group of three birds appeared more than once.
One accepted a piece of Carver’s crusto pie.
All three departed without making a sound.
They returned and watched the party near the Crystal Gardens.
A crow delivered the shadow dragon’s red invitation to Castle Avernus.
Carver detected transmutation magic on a crow at the Two Brothers Creamery.
That crow transformed into Vidic, who said he had watched the party since the garden battle.
Two crows followed the party toward the hidden house, and one transformed into Vidic.
On Richten House’s battlements, two ravens watched separately from an otherwise ordinary flock.
One disappeared downstairs; the other enlarged to the size of a turkey and attacked when Rage charged it.
A giant badger summoned near the domain border caught an apparently ordinary raven.
Faith’s Library contained references to unusually large King’s Ravens once seen around Castle Avernus.
One obscure text called them always watching and somehow “part of Azalin.”
Vidic confirmed that he is a wereraven and member of the Keepers of the Feather.
He distinguished his order from the King’s Ravens associated with Azalin.

Were all three original birds Vidic, other Keepers, King’s Ravens, or ordinary animals working with them?
Did Vidic deliver the Castle Avernus invitation, or was that a different crow?
Who or what else might be observing the party?
What was the enlarging raven-like creature killed on the battlements?
Why do they fly silently?
Which watching birds belong to which raven faction?