So, I was wrong. In the Grave Theif, Tom Lloyd seemed to me to have lost sight of his series, delivering sketchy characters and skipping over key events. Here, suddenly, the action, plotting and characterisation suddenly feel far tighter, and the level of detail and description is ratcheted up a notch.
From the beginning, the description of Mihn's descent into the underworld is tense and gripping, and the action continues with a lot of surprises, twists and very well done set pieces in terms of major battles and commando style raids. My only complaint is that the book lacks a central key figure - not unexpected given Isaac's death at the end of the Grave Theif, but his abscence is noticable.
Still, I was very impressed overall and I am now sure that the final book in the Twilight Realm series will be a good one. I now can't wait!