This is one of the best books a storyteller can have if they are running a crossover game. While very helpful for adjudicating effects on NPCs, it is invaluable if you ever intend to run a mixed party game with vampires, mages, changelings or other supernatural PCs playing together. While written as a companion to the Contagion Chronicle, you absolutely can and should use this book by itself. Fantastic book, exactly what I have been looking for. Cannot recommend enough.

This is what I was wanting out of the Contagion Chronciles. What spheres to affect what splats, what different blood tastes like and how it affects vampires...This is the crossover book for Chronicles of Darkness.

If you're looking for some Chronicles of Darkness crossover, this is 100% worth the price. This book is what was missing from The Contagion Chronicle book because here we get the answers to the crossover questions raised by the "core" book. Now, I LIKE The Contagion Chronicle plenty for what it is, but it kinda promised crossover stuff that didn't QUITE materialize. No, this book won't give you EVERYTHING you may want, but it does make managing werevolves, mages, vampires, and even stranger monsters thrown together into your stories a lot easier. You'll still have to put effort into making it work, but at least you'll have some solid direction. I also love the "peek behind the curtain" vibe of some of the sidebars. Again, so worth buying, even if you don't have The Contagion Chronicle.