The book is supposed to have been written by Eibon, a wizard in the land of Hyperborea. It was an immense text of arcane knowledge that contained, among other things, a detailed account of Eibon's exploits, including his journeys to the Vale of Pnath and the planet Shaggai, his veneration rituals of Zhothaqquah (Eibon's patron deity), and his magical formulae—such as for the slaying of certain otherworldly horrors. Unfortunately, only one complete fragment of the original is known to exist, scattered in different places of our world, though there are translations in English, French, and Latin—"Liber Ivonis" is the title of the Latin translation.