


According to the biographical note on the back cover, Rumstuckle "joined the Wizards' Guild in 1514 and became its youngest president ever seventy-eight years later, a post he holds to this day." The novel stars "you" as you train to become a wizard (in wiccan style). In 2003, Brennan published the children's book The Book of Wizardry: The Apprentice's Guide to the Secrets of the Wizards' Guild under the pseudonym "Cornelius Rumstuckle." The book purports to instruct children on how to become a wizard it discusses crafts such as making a wand, and includes astrological references throughout.

In 1998 he published Martian Genesis an ancient astronaut book which claimed the human race is of extraterrestrial origin. In 1995 he contributed two novels to the Horrorscopes series under the house pen name "Maria Palmer". He later became associated with Dolores Ashcroft-Nowicki and the Servants of the Light. He initially trained in esoteric teachings and Qabalah with the Fraternity of the Inner Light. More recently, his teenage novel Faerie Wars achieved The New York Times best-seller status in the United States and is now part of a five book series. His works have been translated into approximately 50 languages, he has also written books on the Occult and New Age. :165 Brennan wrote several different gamebooks, including a series of eight Arthurian adventures called GrailQuest (1984–1987), and two published only in French – Aztec Quest (1997) and Egyptian Quest (1997). :164 Brennan also designed Timeship, the last roleplaying game published by Yaquinto Publications.

Brennan's Man, Myth & Magic was published by Yaquinto Publications in 1982 he had originally started developing it as a much smaller Roan-themed role-playing game called Arena, but the game continued to grow from its base as he developed it.
