After [b:Blood Magic|6650737|Blood Magic (World of the Lupi, #6)|Eileen Wilks|http://d.gr-assets.com/books/1311703107s/6650737.jpg|6740123], which I found more boring than not, I almost gave up on this series. I love Lily and Rule but there adventures were too far off track in Blood Magic and I didn't like the direction the author was taking this series. I'm so glad that I gave it another try though. Blood Challenge is fantastic and the best in the series so far. Lots of action, lots of simultaneous plots with different factions - fae, werewolves, witches, humans and even an immortal God. This book really ratchets up the tension and stakes. Excellent!