"Deep" is the best word for this book. It starts deep within Satanic philosophy and concept and only goes deeper. It wastes no time explaining the basics of Mysticism or Satanism, it just tells you how to use the former as an approach to the later- Clearly, succinctly, and effectively.
This book is the basic text on how to commandeer Kabbalah for Satanic purposes. I say basic but there can be no advanced text because we are not O.T.O. or Golden Dawn or some textbook adaptable system of how to think. So while it showcases contents superficially similar to the Book of Thoth or Vision and the Voice, it's not the author's occult experience- It's a clear guide on how to take the concepts and practices that make Kabbalah a powerful magical and psychological tool and turn them towards one's self, toward the left hand path, and into the darkness.
I am also happy to say it's not a simple inversion of the principles- It's an application of the same principles for ones own ends. Real ends and not pipe dreams as the systems have always been used for (i.e. "I have seized the true flaming sword of the Archangel Michael from which all power emanates! I shall use it to send happy love vibrations toward all man and womankind!"). The imagery used is also as resonant to Satanic aesthetics as the common "originals" were in their day, for example the idea of falling down the roots of the tree of life, in contrast to the typical climb we have the Fall of Satan.
That's not to imply the book is all general conceptualism, quite the opposite- It gets into details and specifics. The techniques contained within, from ritual outline to a vastly different set of Tarot trumps, are all easily adapted to any (Smart, Satanist) individual with a use for them. Like Magister Rose's concept of Hell as a state of mind, Magister Sprague provides Satanic uses for concepts such as the Tree of Life, 4 elements, gateway-sigils and more. He also grants Kabbalistic applications to the Satanic elements of Sin, personality types, etc. The manner in which he adapts the old creatures is easily applied to any other arts not covered.
The word "Numerology" never even appears in the book but after reading, a numerology buff should have no problem in finding 216 news uses for their preferred art within the Satanic arena. Like all the best Satanic literature, ideas sprout like weeds while reading. This book is a most powerful and versatile tool. It is the Swiss Army Knife of Satanic Magic.