The Necronomicon is a mystical book that tells of the history of The Dreamlands. It was written by a mysterious figure only known as "Abdul Alhazred". No one knows how it came into being, but it's words are known to be absolute truth by those who are aware of the existence of the Dreamlands.
The Necronomicon is known to contain numerous secrets, and many have tried and failed to get their hands on this book.
In truth, the Necronomicon is a living book, and the very source of the power of the Dreamlands. It writes itself, having infinite pages, as the Dreamlands continue to evolve.