Ghudiern

Ghudiern (goo-dee-urn) is a faerie legend who made a pact with Faeghala and together they created the faeghul.

Ghudiern is a ghul daemon leader (their devil).

He is the offspring of Njóla and Vándr Náttúra. He however developed an appetite for eating the dead, and Njóla excised him from Ofantún. He found his way to the caves in the mountains, where one day he found a faerie who was disillusioned with the way of faeries, and was an exile himself. So Ghudiern with the help of the faerie magike created Faeghala, who became the father of all faeghuls. In return faeghuls make offerings of their food to Ghudiern.

Etymology
The term is derived from the words 'ghul', which is Arabic for ghoul, and 'diernan' and Old English phrase meaning 'to hide'. So the term literally translates to the 'ghul who hides', which is in reference to the fact that he hides in the caves.