
Demon Marbas is described in many old Occult sources: Goetia, Pseudomonarchia Daemonum, The Discoverie of Witchcraft, The Grand Grimoire, The Book of Oberon and other books.
Below you will find good information about Marbas and it will help you to summon this spirit.
Demon Marbas: Pseudomonarchia Daemonum

Marbas is a president and he appears in the form of a huge lion. He can take on human shape too. Marbas can answer your questions about things secret and hidden.
He brings diseases and cures them too. Marbas makes a man wise and gives very good knowledge of mechanical arts and handicrafts. He changes people into other shapes and he commands 36 legions of spirits.
Source: Johann Weyer, Pseudomonarchia Daemonum
Demon Marbas: Goetia
Marbas is the 5th spirit and he is ranked as a President. He appears in the form of a large lion, but then takes on human shape. Marbas answers truly of secret and hidden issues.
Marbas causes diseases and cures them too. This spirit gives great wisdom and knowledge in mechanical arts and he can also change people into other shapes. At last, Marbas rules over 36 legions of spirits.
Source: Goetia
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