From the publisher:
Restraint, restriction and self discipline define the
Forbidden's life. The Forbidden is instantly recognizable by his distinctive costume and all concealing mask. The Forbidden draws great mystical power from their obsession with concealment, with secrecy. The leather and steel face they show the world becomes a part of them, and most Forbidden view their mask as a truer indication of who they are then the flesh and blood face they were born with.
Forbidden do not gain their power from study, and ancient spellbooks hold little interest for them. Instead, the Forbidden draw their power from within, focusing their will and intellect to the point they can accomplish incredible magical and psionic feats through sheer determination. Some Forbidden embrace disciplines as diverse as monastic self flagellation, ki-focusing kung fu, bondage lifestyle elements, modern psychotherapeutic techniques and cult leadership tactics. Regardless of where their inspirations come from, the Forbidden uses their diverse array of skills and psychic gifts to shape the world in the same way they shape their body.