This is an interesting class, but could use some rebalancing to make it more effective at low levels. It has several features such as tethering spirits and crafting focus items, but doesn't provide enough guidelines (I feel) for a player to get a grasp on what he can do with the class, or a GM to arbitrate what shouldn't work. I would also have enjoyed an expanded section on the nature of various spirits in the spirit world (the thematics here remind me a bit of spirits in Runequest) as spirits are a new concept to PF/3.X as presented. The book is very clean otherwise and nicely illustrated. If your game is full of god role-players and no rules lawyers you will probably get the most mileage out of this book, but do not let cheesers get their paws on it, as the free-form nature of spiritual benefits a shaman can gain are easily abused.