The Forbidden City
(1986)(The second book in the World of Lone Wolf series)
A non fiction book by Joe Dever and Ian Page
The Wytch-king will try to track you down. His slaves will dog your every step -- the cruel warriors of Shadaki, the phantom spirit of the Deathgaunt and the dark horror of the demon Kleasa. Only your magical powers and the might of your Wizard's staff can protect you in a terrifying adventure of madness, magic and menace!
Used availability for Joe Dever's The Forbidden City