Legacy of Blood is one of the greatest books to purchase to make your Ravenloft Campaigns stand out. In Ravenloft you can't always go against the Darklords simply because that sometimes wreak havok on the carefully constructed world. On the other hand players want to be a part of the world and interact with it. Legacy of Blood helps bridge the gap, in it you will find classical Ravenloft Characters as NPC such as Eva Mordenheim, Sir Viktor Helsinger, Talen Von Zarovich, and many more. You are also given the unique ability to stat and make your own decendants of such families as the Von Zarovich's, the Mordenheim's, and the Godefray's to name a few. When creating these characters you will find that each family starts off with some wonderful merits and some family flaws. Each of which has a set of family feats which enhances your core families reputation rather well. The book also gives you some prestigue classes that help further cover the topic of gothic science, war, diplomacy, revolution, and sorcery.
I would recommend using this Book to players of Ravenloft and DM's both can use this book to create Characters with ties to the Dread Realms. I'm thrilled that they produced it and it can only add to the potentional of any Ravenloft game.