Crúac
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The ritual blood magic practiced by the Circle of the Crone. Crúac rituals always require the sacrifice of Vitae. Crúac has a singularly insidious drawback: advancement in the knowledge of Crúac comes at a terrible price to The Man, as the knowledge of Crúac's more powerful rituals serves to strengthen The Beast at the expense of The Man. (VTR: Vampire: The Requiem Rulebook, p 142)
