Seals and characters for summoning the greater demons Lucifer, Beelzebub, and Astaroth. In order of effectiveness, the symbols must be drawn in either: the sorcerer’s blood, the blood of a sea turtle, or engraved on emerald or ruby. From Grimorium Verum (16th Century) and The Grand Grimore (18th Century). Source: “The book of black magic and of pacts”, A.E. Waite, Embassy of the Free Mind

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