3.75 stars rounded up
I felt that some parts were dragging the story down (initially, wasn't a huge fan of the alternate realm plot); plus it had TOO MANY new players added; McHugh probably setting it all up for the next book as the final one. But I'm still rounding it up because the last 1/3rd was too much awesomeness...
+ Mordred. I was highly excited with this new development of him. I loved reading him partnering with Nate
+ Francis and Brutus' death. Those were jaw-dropping moments.
+ Finding out Kasey's elemental power in addition to her being a werewolf.
+ We finally found out that Nate's mother was a Valkyrie, Brynhildr
+ Nate gained another power, shadow magic, and it KICKED ASS (the wraith is awesome)
+ Merlin supports Hera. He is a total douche and he proves it more and more in each book
+ DRAGON SIGHTING!
+ OMG ARTHUR IS AWAKE!
I am thinking about who's behind everything. I mean, Hera's is quite the "top goddess". If she works for this "My Liege" character, then he (or she) must be someone so powerful that even Hera follows him (or her) around. So all I could think of is a Titan. Like
Kronos (or Gaia, because let's face it, Rick Riordan showed that Gaia could be crazy as well). That is the only possibility I can think of. Unless if McHugh decides to bring king of demon like Lucifer to this series as well.
(show spoiler)