I had bought this book when it first came out several months ago, and I was very excited to read it. The Battle of Calth is one of those legendary events in the Warhammer 40K mythos, and I could not wait to see how it would be expanded upon as a Horus Heresy book. Furthermore, First Heretic (by Aaron Dembski-Bowden) did a great job of setting up the Word Bearers and what events led to the Battle of Calth, so Know No Fear was the sequel or continuation, which was exciting. However, I had a huge stack of books, so I had originally decided to wait until I had time to read it and enjoy. Then, I became ill, and my reading was thrown off for months as a result. Slowly, as I was able to read again, I read The Emperor's Gift and Treacheries of the Space Marines. Now, I'm back to full capacity, and I decided to finally read this one.
Now, Dan Abnett is worshiped by some, and reviled by others. As for me, I think he's really, really good, but he does write clunkers. I absolutely loved the Eisenhorn Trilogy, but thought that the Raevnor Trilogy was lackluster. Prospero Burns was solid (if offbeat). I was anxious to see where Know No Fear would fall on the Abnett spectrum. Making it more complicated, this book would be following the lead of First Heretic, which is simply one of the best Horus Heresy books yet- could it possibly compare?
The answer is- absolutely!! Know No Fear is a fantastic read- it has it all, so many ideas, so many action beats, great characters, and it concludes some Heresy threads while continuing others (John Grammaticus, for example). It has suspense, a bit of humor, a great sense of scope, and relentless pacing.
The set up is this (no spoliers, as any 40K fan knows the basics about the "Muster at Calth"): Warmaster Horus has ordered that the Ultramarines link up with the Word Bearers on the Ultramar world of Calth and unite their forces to crusade against nearby Orks. Of course, the Ultramarines and Word Bearers don't quite get along, but the Ultramarine Primarch, Roubute Guilliman (well written by Abnett) figures this is just Horus' way of getting the two legions on the same page. Little does Guilliman know that Lorgar, Primarch of the Word Bearers, has embraced the gods of Chaos, converted Horus to the same gods, and is planning to tear the galaxy asunder. However, for that to be achieved, Lorgar needs to decimate the Ultramarines, and the gathering on Calth becomes the method to betray and destroy the Ultramarines.
The book is expertly placed, with the opening chapters reading like a thriller- you know bad stuff is about to go down, and it's great at making it suspenseful. Once the Word Bearers make their move, it becomes hugely tragic- the scale of the destruction is vast, and the Ultramarines are so slow to react, since they don't even know what's happening. The second half of the book deals with how Guilliman and his legion try to fight back- the battles evoke everything from Lord of the Rings sieges to a Star Trek: First Contact style spacewalk battle (wait till you read it- and that cover... wow!). Even if Guilliman can triumph, what will be left of Calth? And the galaxy itself?
Though the Ultramarines are the heroes, if you've read First Heretic, you know that it's much more complicated than that. What the Ultramarines did on Monarchia (under the Emperor's orders) to the Word Bearers- is it really all that different to what the Word Bearers want to do to Calth? Abnett plays that very cleverly- he does a great job of comparing and contrasting Lorgar and Guilliman. One writes constantly about "faith", while the other writes about "strategy". Both are more than simply warriors; they are philosophers, father figures to their legions, etc. They are also the sons of the most powerful, if seemingly flawed, man in the galaxy- a difficult legacy for both Primarchs to live up to- Guilliman tries to be prefect, while Lorgar has given up. There are a ton of comparisons to make, and by doing so Abnett really goes beyond simple "good" and "evil". Does "an eye for an eye" make the galaxy go blind? The Horus Heresy has become even more complex, and that's a good thing.
I don't want to give too much away- the battles are so vivid, and the strategies developed by the Ultramarines (the practical and the theoretical) are so well done by the author. The game of 40K really comes to life in these pages, and the drama of these two legions fighting one another makes it a great story. My only complaints are that there are too many characters to keep track of (especially at first), and that some threads are kept hanging (though, like John Grammaticus, there are threads that will pop up in future books). That said, I can't recommend this book enough. Just know that you SHOULD read First Heretic beforehand, otherwise you're only getting half of a great one-two punch. I give this book 4 out of 4 Marks of Chaos. If you are a Heresy fan, an Ultramarine or Word Bearer (or just Chaos) fan, you must read this book, its that simple.