From the back of the book:
"Cults of the Young Kingdoms details the cults offering pacts with the Lords of Law, Chaos and the Elements. Expanding on the cults presented in the Elric of Melnibone rules, characters have greater scope for worship, more Gifts and Compulsions, and additional powers - if they are prepared to enter into a Pact with the higher forces. The Elemental Lords and several new, personality and ancestor cults are also detailed, deepening and widening the scope for worship and dedication, and fueling the need for adventure.
Each cult is provided complete: history, purpose, religious rites, forbidden knowledge and special notes regarding their place in the cosmic hierarchy and in relation to each other. This is the most detailed treatment of Young Kingdoms religions ever presented, and offers a treasure-trove of possibilities for characters and Games Masters alike."