From the back of the book: "Ancient cosmic terror looms over your campaign in this lavishly illustrated d20 book, fully compatible with any d20 setting. Five dark entities rule over five different aspects of fear: Disease, Madness, Blood, Darkness and Savagery. They lurk in Nephandum, and now they are about to take over your campaign! The GM can freely choose the preferred degree of influence and the style of play. Be prepared to face your worst fears and start a thrilling journey that will lead you into the darkest reaches of this dynamic campaign setting. Things will never be the same again!"