Samiel was once again closer to completing the Necronomicon... now that he found the Basic Principles of the Mythos Necrosis...
Grimoires of the Necrosis Series were once part of a greater thing... a book called Necronomicon. It was an enormous grotesque grimoire written in the long-forgotten past several Eras ago by a man called Abdul Alhazred.
Nowadays, not many, even in the Hall of Kadath, aside from the high-ups, were even aware of the existence of the Necronomicon and the fact that the book existed in its shattered form in the Material Plane of the Cosmos.
Something happened that nobody knew, but the Necronomicon was shattered into several parts that Samiel was searching for.
The books contained tremendous power and there was a legend that once they were put together and Necronomicon was once again complete, it would show its true power.