1264 pages, in large format only. For reference: Magician (Riftwar Saga) by Feist, Raymond E. 545 pages.
I've seen some cult books that were physically big and very thick. Author was a junior officer in the USN during WW II (hint hint). The secret was the BIG PRINT and mind numbing gibberish. El oh El. Just read in Red Army Tanks of WW II that the Soviets interpreted the USA stenciled on American lend-lease products as Ubiyat Sukinsyna Adolpho or Kill that Son of a Bitch Adolph. Learn something new (and useless) everyday!
Amber is thword and thorcery. It's got as many sides as a marble. I read them as they were publish. Found the second book in a book store in Callao, Peru, harbor for Lima. Nice find. That was 197mumble.
Since magic was mentioned, the only book I read about magacians is the one about Jasper Maskylene, The War Magician. A lot of the claims are unsustainable but it would probably make for a good flick. Among the anomalies I couldn't ID the ship in Egypt that he purported disguised to look like a battleship.
I read the Great Book about once every ten years. Just starting the tenth book now, so I probably won't do the cycle again. (I flippin' hope not, anyway.) Which brings me to: I'll send you my copy if you'd like to take a shot at it. Zelazny is one of the greats of the 20th C. His GAIA trilogy is another favorite of mine.