The Grimorium Verum (sometimes spelled Grimoirium) is one of the most diabolical black magic works ever crafted within the occult. From summoning Beelzebub and Lucifer to using the head of a dead man and some beans to summon a demon and gain invisibility, much of its content is purely demonic in nature. Infamous for such content it enjoyed hefty circulation in the era of works like the Petit Albert and Grand Grimoire.