These are actual myths that are used in the story Darkened Skies.
Abaddon: Literally means "Destruction" and "Ruin" in Hebrew. It is the name of the demon that is the 'angel' of the abyss in Revelation, 9, 11. Is also known as the destroyer and is one of the destroying angels in the Apocalypse. Abaddon rules over the seventh hierarchy and is the king of the demon locusts, which are creatures that have the heads of humans, the bodies of winged horses in war armor, and the deadly tail of scorpions. The Old Testament uses the name Abaddon to describe the place of the dead.
Beelzebub: One of the oldest and most famous of the demonic figures, he is the incarnate of one of the "Seven Deadly Sins", gluttony. His name means "Lord of the Flies" in the Hebrew language and he has control over all of the insects as well as disease. His role is also one that tempts man, normally with excessive food or drink, leading to the detachment from other ties and the loss of gratitude. He is called the 'Prince of Demons' in some religions and is next after Lucifer and Satan in power.
Leshii: The guardian of the forest in Russian belief. (The word les means Forest in Russian) A shape shifting mischievous creature that could become a small blade of grass, or something as large as an ancient tree. Its most common animal transformation is that of a large black wolf and when it shows it self in man form, it is a large person covered with wild black hair from head to foot. It often makes pacts with hunters and shepherds that use its forest. They often leave out bowls of porridge to appease the Leshii, so that it doesn't harm them. People can conjure the Leshii by making a circle of young birch branches, all of their tips facing the center. Then enter the circle and face east and say this chant "Uncle Leshii, ascend. Do not come as wolf or as a fire, but come in human form."
Lilith: A succubus who is the most important Jewish member of that species. Ancient stories call her the "Queen of the Night" and also tell of her acts against men. She is also known for the death of many human infants, which are said to be her favorite meal, aside from men's souls.
Lucifer: In Latin, his name means "Light-bearer" or "Light-giver" and he is often confused with Satan. He is also one of the "Seven Deadly Sins", pride. Because pride is considered the root of all evil, Lucifer holds the highest place in the demon hierarchy. it is said that Lucifer was the name that Satan had before his Fall From Heaven, where he was very prideful and would seat himself upon god's Throne whenever God was not around. Because of this, the archangel Michael started war with him and his followers and banished them to earth, where Lucifer became Satan and the angels that followed him became the demons that he ruled over.
Mammon: His name is the Syrian word for 'money' or 'riches' and he became known as the Deadly Sin of avarain(Greed). He is often depicted riding a wolf from the mouth of Hell, where he leaps forth to taint the human heart with the love of money and nothing more. Because of his evil touch, there arouse thieves, misers, and murderers.
More to come!
All information comes from "A Field Guide to Demons, Fairies, Fallen Angels, and Other Subversive Spirits" by Carol Mack and Dinah Mack, and Occultopedia.com, so check those out for further information on this subject.
Comments? Questions? E-mail me!
