A sacrifice at a dark altar is rewarded.
A black dagger.
Bring a corpse to the altar and offer a sacrifice.
Go and kill something to produce a corpse (You can find plenty of A bloated toad, A half-starved black rabbit in the area in one of the Outside Asturasartes rooms) then return to the altar.
place corpse on altar
After a short scene a figure will come to you and give you your reward.
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