Oberon Zell-Ravenheart

During a routine colonoscopy, doctors found a cancerous growth attached to Zell's colon, and removed it laparoscopically at Petaluma Valley Hospital. Following surgery, he underwent a six-month course of chemotherapy and has continued a reduced schedule of travel and teaching. Another surgery repaired a hernia at the cancer surgery incision in August 2009, but was otherwise not cancer-related. Zell regards himself as cured of the cancer. He resided in Sonoma County, California, with Morning Glory until her death at age 65 from multiple myeloma on May 13, 2014.

In an interview with Natalie Zaman in 2008, Zell described himself as a wizard. Distinguishing his practice from the wizards of fiction, Zell used the alternative spelling magick (with final "k") and claimed that his interest therein began at an early age with the reading of Greek myths and fairy tales. As a child, Zell had visions, which his mother told him were derived from the life of his grandfather.

The Grey School incorporated on March 14, 2005 as a non-profit educational institution in the State of California. The school grew from lessons originally created by the Grey Council, a team of two dozen practitioners, who with Zell-Ravenheart, wrote the Grimoire for the Apprentice Wizard and later the Companion for the Apprentice Wizard. While initially conceived for ages 11–17, the school accepts adult students. The school comprises sixteen departments of study, various clubs and organizations, a forum area, a prefect/captain system, opportunities for awards and merits and a house/lodge system for adults and youths in which they can communicate directly with each other. Youth (under 18) students are sorted into four houses: Sylphs, Salamanders, Undines, and Gnomes. Adult (18+) students are sorted into four lodges: Society of the Four Winds, Order of the Dancing Flames, Coterie of the Flowing Waters, and Circle of the Standing Stones.

Zell-Ravenheart co-founded the Ecosophical Research Association in 1977, an organization that explores the truth behind myths. This group was known for the "living unicorns" they created by minor surgery to the horn buds of goats, a technique he was granted a patent for in 1984. One of their unicorns, Lancelot, toured with the Ringling Bros. and Barnum & Bailey Circus.

An early advocate of deep ecology, Zell-Ravenheart claims to have articulated the Gaia Hypothesis (using the spelling "Gaea") in 1970, independently of James Lovelock, who is usually given credit. Along with his wife Morning Glory and the other members of his group marriage, he has been influential in the modern polyamory movement.

As the creator and original editor of the Neopagan magazine Green Egg in 1968, Zell-Ravenheart was an early popularizer of the term "Neo-Pagan". When Green Egg began publishing as a spirit-duplicated newsletter, Zell used the term "Neo-Pagan" to describe the new religious movement he was helping to create. Green Egg later grew to be a semi-glossy magazine with international distribution and, in an era before the Internet, its letters column provided a widely distributed public forum for discussion and networking. Green Egg is currently published as an online magazine, edited by Rev. Alder Moonoak.

Zell earned a Bachelor of Arts degree in psychology from Westminster College in Fulton, Missouri, in 1965 before briefly enrolling in a doctoral program in clinical psychology at Washington University in St. Louis. He also received a Doctor of Divinity degree from Life Science College in Rolling Meadows, Illinois, (a defunct nonresidential seminary analogous to the Universal Life Church) in 1967. In 1968, he completed a teaching certificate at Harris–Stowe State University. His parents were Protestants.

With R. Lance Christie, Zell-Ravenheart formed the Church of All Worlds (CAW) on April 7, 1962, by the ritual of "sharing water". This foundation ritual was practiced by a fictional church of the same name in Robert A. Heinlein's Stranger in a Strange Land. Zell-Ravenheart and Christie attributed their inspiration to Heinlein's novel. From the 1960s through the late 1990s, Zell-Ravenheart served as High Priest and Primate of the church. He returned to lead the Church of All Worlds, Inc. in 2005 and currently serves as First Primate.

Oberon Zell-Ravenheart (born Timothy Zell, November 30, 1942, St. Louis, Missouri; formerly known as Otter G'Zell) is a Neopagan writer, speaker and religious leader. He is the co-founder of the Church of All Worlds.