From the publisher's website: The free serialized version from several years ago has been added to, scrubbed, edited, and generally improved upon. The adventure now is self-contained, from the surface ruins to the dreaded lowest levels, with a separate map book and illustration book (with pictures to show the players what they see at given places in the dungeons). User note: This megadungeon requires three books: Castle of the Mad Archmage Adventure Book, Castle of the Mad Archmage Map Book, and Castle of the Mad Archmage Illustration Book.