The Leviathan was a shadow beast from the Abyss that was invoked by Cardinal Ambrosio Luis Monçada to act as guardian to his haven in the catacombs of the Iglesia de San Nicolás de las Servitas (Madrid, Spain).
The Leviathan is described as a tide of darkness, a legion of tendrils with a grip of stone. Darkness was its strength, and as it grabbed its victims, the blackness was complete. Those unfortunate enough to be caught by the creature's embrace could hear the screams and trapped echoes of despair voiced long ago by tortured penitents.
Eventually the creature was made confused when it was ordered to destroy Monçada's childe, Lucita. The creature recognized Lucita's blood as Monçada's own, and attacked the Cardinal, giving Fatima al-Faqadi the opportunity to end his unlife.
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