The vast majority of my Black Library reading has been confined to the "historical" side of 40K. Outside of a few Guard-centric novels and an Omnibus of short stories my reading has been firmly entrenched in the 30K universe of the Horus Heresy series. So, for me, Aaron Dembski-Bowden's Soul Hunter has the distinction of being several firsts. It's my first 40K novel centered on Astartes. It's my first-ever experience with the Night Lords legion. And it's my first novel featuring a traitor legion from cover to cover. After reading Soul Hunter I can honestly say that I want none of these firsts to be lasts.
Many readers/reviewers tout Dembski-Bowden as having made the first novel where they actively root for Chaos or sympathize with a Chaos marine. I refuse to give him credit for that, because it's not what he's done. In fashioning the Night Lords, Dembski-Bowden has deftly made the distinction between a Chaos Legion and a Traitor Legion and, quite smartly, given us the latter.
As the book opens, the Night Lords are a Legion in disrepair. With no homeworld to recruit from and no ruinous power to back them, they've spent the last 10,000 years on the losing end of a war of attrition. They scavenge their equipment from slain Astartes, friend or foe. These are not the defiant heroes, or conquering villains we've come to expect in power armor. But Talos, our titular character and ersatz leader of 10th Company's 1st Claw, has a sense of duty and responsibility to his battle-brothers that reads pure Astartes. Formerly an Apotehcary, he is acutely sensitive to the needless loss of personnel given the Night Lords' current state-of-affairs. He just happens to be Astartes in a legion that doesn't subscribe to humanity's God-Emperor.
That's not to say the book is Chaos free. Several characters within have been tainted by the ruinous powers, and it's through these characters that Dembski-Bowden makes the distinction between traitor and tainted.
The Exalted's is a grotesque and unsympathetic character. His reckless use of dwindling personnel is diametrically opposed to our main character's view, and shows just how far removed The Exalted is from being Astartes. (I did find myself unexpectedly admiring his prescience for void warfare.) Uzas is similarly unsympathetic with his one-tracked Khornate ramblings. And, in what is perhaps the coolest cameo I've ever read, Abaddon The Despoiler, 40K's king of all things Chaos Marine, has all the soldiers and equipment he could hope for, and precisely zero redeeming features.
It's through Talos' interactions with these characters, and their followers, that we see who the Night Lords are. It's in flashbacks to days of the Great Crusade and Horus Heresy that we see how they became that way.
Prior to Soul Hunter all I knew of the Night Lords was that they wore blue and liked wings, fangs and lightning. I imagined them as the "evil" counterpoint to the Blood Angels. From Conrad Kurze's early days in Nostramo Quintus to his eventual demise, I was pleasantly surprised at their history. They don't dress like death and scary because they're tainted, or because their Primarch is a vampire. They dress in death and scary because their dad was a murderous Batman and psychological warfare was his bread-and-butter.
This doesn't help so much when you're fighting the Adeptus Mechanicus. Fortunately for us, even when the Night Lord's specific talents don't come to bear, Dembski-Bowden's talents do. He handles action sequences well, giving just the right balance between description, pacing, and badassery. What's most impressive is that he strikes the appropriate balance no matter the battlefield or combatants. Whether it's the delicate ballet of ships in space, the primal mob of rioting prisoners, or a one-on-one duel between a trained warrior and an assassin, he keeps the action lively and the pages turning.
If there's one flaw in the book, it's that it's obviously written to be a part of a larger whole. Granted, I want to read the rest of that whole, but I was a little disappointed at where the novel ends. In my mind, we've just started to explore the most interesting character developments and interactions, Septimus and Octavia chief among them. As the only humans we see past single vignettes, I'm as intrigued to find out what happens to them as I am the main character and the legion.
Overall, the book feels very much like the first in a series instead of a self-contained whole with threads arcing into larger plot. If that's not your cup of tea, I'd suggest waiting until the rest of the series comes out before picking it up. If that doesn't bother you, Soul Hunter is a quick, entertaining, and illuminating read. It has depth without being obtuse, and just enough "that is SO cool" to make me want to emulate it on the gaming table.
Now that Dembski-Bowden has had a chance to set-up his little section of the universe, I'm intrigued to see what he does when his only obligation is to play in it.