Aaron's books are known for the layered depth he manages to bring to our favorite post-human warriors and their liege lords and Betrayer is no different. The story picks up immediately after The Butcher's Nails and a few months or so after Isstvann V with Lorgar's Shadow Crusade in Ultramar in full swing. Without spoiling to much, the goal of the crusade is to finalize the process that Erebus started on Calth and cut off the Ultramarines from the rest of the Imperium. This is done through copious amounts of bloodshed as they slaughter their way from planet to planet.
The real meat of the story are the characters and this book follows several. If there was one weak point I had to pick on for this book its that I don't really know who our main protagonist is supposed to be, it is more of an ensemble with no central emphasis. On the Word Bearer side of the novel we follow Argel Tal, Lorgar and a few other surprise secondary characters and with the World Eaters we get Angron, Kharn and Lotara, the ship captain for Angron's flagship. We see the effects of the Butcher's Nails on the legionaries and the degradation of the World Eater's legion as a whole. This is given even more contrast by the inclusion of Lhorke, the former Legion Master from before the reunion with their Primarch and currently a contemptor dreadnought. Lacking the Nails and having been in hibernation for extended periods of time he sees the degradation of the legion in even more personal terms. This novel continues the trend of seeing the traitor legions fall more into the embrace of Chaos, especially the Word Bearers. The World Eaters have the Nails to blame where as Lorgar's lot has no excuse.
Lotara is quite an interesting character in that she is a mortal and shows almost no fear towards Angron or Kharn, the latter of which is a good friend of hers. She clearly has rank on several of the legionaries and flexes her power on a few occasions which is a new dynamic we don't see very often. Aaron seems to have a penchant for writing strong female characters in a lead role in most of his books, Lotara, Cyrene, the Fenresian Inquisitor from The Emperor's Gift, again a nice change of pace from what we normally see in 40k fiction which is dominated by overly muscled men. Having just seen the new Mad Max movie, I would have to compare her to Furiousa in terms of a strong female character.
One of the more interesting inclusions in the novel is Magnus, not someone you would expect to see in a World Eater centric story. Lorgar and him have a very genuine and believable friendship and when you no longer have a physical body and are the second most powerful psyker in the galaxy, time and space don't pose much of a problem. Angron's story is fleshed out a lot more with much of his mysterious past explored in a believable and emotional manner. One of my favorite things about him is the way he speaks, with frequent "hngggs"s and other guttural noises scattered throughout. This makes it very enjoyable to read his dialogue and brings another level of realism to the whole affair. Kharn and Argel Tal are the only stable tie between the two legions, both of whom seem pretty disillusioned with the war. Kharn is strangely sympathetic considering what we know he becomes in the future, which makes his eventual fate even more tragic. He seems to be the only one who can still think clearly, well, most of the time. Argel Tal's story in this novel revolves around his brotherhood with Kharn, his last true friend. The First Heretic dealt with his faith and his fall from grace while here we see him trying desperately to hang on to the last thing that grounds him and makes him human. While their story is interesting they are out shined by their Primarchs.
The battles are fast paced and interesting with a little more realism then what is generally shown in the Black Library novels. City warfare has never seen more brutal and intense then on Amutara. Some of my standout moments include a collapsing cityscape, a desperate boarding action, violent planetary forces and a duel for the ages.
This is one of those rare Black Library novels where the action is intense, the characters believable and the quieter moments are deep and revealing all in equal measure. It was hard to put down and I am strongly looking forward to Aaron's next Heresy novel, and with a title like The Master of Mankind who wouldn't be?
Ready the Ursus Claws! - 5/5