Belisarius Cawl: Archmagos: Warhammer 40,000

by Guy Haley, John Banks (Narrator)

A Warhammer 40,000 Audiobook

Belisarius Cawl is the greatest mind of his age, and he has a plan to open up the Attilan Gap to allow safe passage through the Great Rift. In order to complete his work, he travels to a necron tomb world. In the process, he attracts the attention of something even more dangerous than ancient xenos…

LISTEN TO IT BECAUSE
Belisarius Cawl continues to be one of the most important figures in the 41st Millennium as he attempts to solve the greatest problem facing the Imperium – allowing safe passage through the Cicatrix Maledictum. He squares off against ancient necrons and the forces of Chaos in his audacious attempt to do the impossible.

THE STORY
For years, Belisarius Cawl has nurtured an audacious plan to stabilise the Attilan Gap sufficiently that the Imperium might open a stable route into Imperium Nihilus. With the primarch Roboute Guilliman having crossed the Great Rift, and now isolated on the far side, time is running out.

Before Cawl can perfect his latest great work, he requires one last control codes preserved on an ancient necron world trapped on the event horizon of a black hole. Realising that even he cannot do this alone, Cawl recruits help from across the Adeptus Mechanicus. Yet as victory nears, malign intelligences have taken note of the archmagos, and Cawl is about to discover it is unwise indeed to provoke the interest of Vashtorr the Arkifane…

Written by Guy Haley. Narrated by John Banks. Runtime 10 hours and 52 minutes approx.

Genres: 40k, Science Fiction, Audiobook, Novels

Audible Audio

Published November 21, 2025

About the author

Guy Haley is the author of over 50 novels and novellas. His original fiction includes Crash, Champion of Mars, and the Richards and Klein, Dreaming Cities, and the Gates of the World series (as K M McKinley). However, he is best known as a prolific contributor to Games Workshop's Black Library imprint.

When not writing, he'll be out doing something dangerous in the wild, learning languages or gaming.

Reviews

[Jordan · Rating 5 out of 5]

fantastic read! i couldn’t put it down!
(& most importantly.. is the narrative finally moving forward!?)

guy haley is no stranger to cawl and ‘archmagos’ really solidifies that. you can tell how passionate he is about this character and we’re fortunate enough to be a part of their journey.
this book from beginning to end was very high pace and so incredibly immersive. this will absolutely be added to my re-read list!! i can’t wait to experience it again.
avoiding spoilers (because it’s a brand new book after all), i think readers will be happily surprised where the story goes!

welcome back mr. haley and welcome back cawl. that was awesome.

[Wish · Rating 2 out of 5]

Having recently read The Silent King also by Guy Haley I have to say that I am surprised that I still read Warhammer books and that if this is what can be expected in future then I will likely stop reading these books.

Both Archmagos and The Silent King are "event" books instead of really focusing on the titled characters. In the past I have enjoyed books with Belisarius Cawl, especially Genefather. This book does show Cawl being eccentric, interesting and a heretic by acting brash and striving for innovation. However, there just isn't enough of anything else that would encourage a reader to continue. Lots of time is devoted to some poorly defined chaos characters and again the boring necrons show up in this book.

Does the reader learn more about the origins of the Archmagos? No.
Does the reader learn about the Archmagos' fears, inspirations or early life? No.
Does the idea of the Archmagos as a character sound good? Yes, just give us more details.

The story in Archmagos is meant to push the Meta-Lore forward by about two millimeters over almost three hundred pages. Subjectively, I don't care about the meta-Lore and what is being built up or foreshadowed because this type of story telling usually leads to weak or anti-climactic endings. The Archmagos does indeed conclude on a weak note and prepares the reader for "more". Except, the Warhammer universe already has so much history that I wish readers could get stories that really dig into famous people and their lives.

Why is Fulgrim obsessed with perfection?
Why was the Emperor so distant to his sons?
Why is Mork greater than Gork, or Gork greater than Mork?

Instead, Games Workshop keeps shoveling out slop as if the best fit for the lore is the Saturday Afternoon cartoon template. I don't recommend this book to old or new fans of the Warhammer 40K lore.

[Andrew · Rating 4 out of 5]

I could read Haley write Cawl until the end of time. It is always incredibly fascinating and never disappoints.

Great read!

[Lensvol · Rating 5 out of 5]

Rather nice if you page through all the bolter porn.

[Anibal · Rating 5 out of 5]

Archmagos is a sequel to The Great Work. You should also read Genefather before starting this one, particularly regarding Qvo-89, Alpha Primus, and the Dark Mechanicum (but it is not strictly required). What matters is this: Guy Haley once again proves that Belisarius Cawl is one of the most brilliant, entertaining, and genuinely different characters in modern Warhammer 40,000 fiction. Yes, it’s always genuinely surprising to read books starred by Belisarius Cawl.
This is arguably the most “Jolly god chap” version of Cawl we have ever seen: polite to a fault, absurdly confident, cheerfully heretical, speaking in outdated British idioms, cracking knuckles before action, and referring to his last organic limb as his “serious hand.” He is a pompous, mischievous genius and Guy Haley knows exactly how funny that is.

Despite being an Adeptus Mechanicus novel filled with technobabble, the density of concepts never hurts the pacing. On the contrary, one of the book’s greatest strength is how it balances vast, abstract technological ideas with character-driven humour and tension.

The novel is structured around three parallel plotlines, Let’s call it “Crazy Plan”, “Bolterporn” and “Lousy negotiators” which initially seem independent but gradually interlock into a single, elegant mechanism. Haley deserves real credit here: none of these plots feel redundant, and each reframes the others in retrospect.

Archmagos is highly ambitious, funny, surprisingly warm, and conceptually bold for the WH40K lore development. It balances absurd genius with real emotional weight, and uses its three plotlines to explore time, responsibility, and the cost of progress from multiple angles.

Highly recommended, especially for readers who enjoy big ideas, strong character work, and Warhammer stories that dare to push the setting forward rather than merely orbit it.

Now, the next sections will include a massive amount of spoilers, so beware. If you want to be surprised by the amazing story weaved by Haley please stop here. Below you’l find some ideas and commentaries about each plotline and also what the ending imply for the Warhammer 40K future stories.


Crazy Plan: Cawl, Solana, and the edge of time
The core narrative follows Belisarius Cawl and Solana of Mars, a human Historator sent personally by Roboute Guilliman to keep an eye on him. Solana serves as both investigator and audience surrogate which is both skeptical of Mechanicus dogma, unimpressed by Cawl’s casual heresy, and increasingly alarmed by the scale of his ambitions.
Cawl reveals that he has successfully replicated Necron pylon technology. His pylons are cruder, less elegant—but functional. The problem is not hardware, but software. To activate a full pylon network, he needs uncorrupted Necron data from the War in Heaven itself.
To obtain it, Cawl devises one of the wildest plans in modern 40k fiction (which is by default rather wild):
Travel to a Necron World Engine trapped on the edge of an artificially created black hole, frozen in time for over 60 million years. Using a temporal “tunnel” and a mobile bubble of normal time, powered, of course, by the severed and extremely annoyed and resentful head of a Necron Chronomancer which is now familiar to us from previous installmentsCawl. Cawl leads an expedition into a battlefield from the War in Heaven itself.
Frozen Eldar, Necrons, Dolmen Gates, Flayers suspended mid-attack, and a living World Engine whose “spirit” actively wants to be decrypted make this section feel utterly alien in the best possible way. It is effectively time travel without breaking the setting, and Haley handles it with intelligence, restraint and clarity.
Here, Qvo-89 shines. No longer just a fragmented echo, he embraces his identity as Cawl’s friend. When he interfaces with the Necron datacore, he becomes something more complete—acting as both key and vessel for the data, briefly reuniting with Cawl as their ancient selves. It’s a surprisingly emotional moment in a novel about impossible technology.
The result: pure, unpolluted Necron knowledge, straight from the War in Heaven.


Bolterporn: Decimus Felix and the long wait
Running parallel is Tetrarch Decimus Felix, sent by Guilliman to observe Cawl’s experiment on Ulvheim, homeworld of the Wolfspear Chapter. There, a small, experimental pylon network is being constructed to seal the Pit of Raukos, a minor but persistent warp rift.
Felix’s plot is deliberately slow and that is the point. While Cawl experiences only hours on the frozen world, months pass elsewhere. Felix and the Wolfspears endure nightly daemon assaults, feasting by day and fighting by night in a grim Valhalla loop.
When Vashtorr’s influence escalates the threat, the scale shifts dramatically: hundreds of Soul Grinders descend before sunset itself. Haley handles the ensuing battle with refreshing realism with fortifications, orbital fire (yes! Marines use Orbital fire! It appears so rarely we even forget that ), artillery, and even with all the military strengths they deploy the Space Marines are slowly overwhelmed. Of course the usual duel between main champions will be fought between two major characters.
This plot grounds the novel emotionally. Felix is older, burdened by governance, and painfully aware of the cost of Cawl’s genius. His final confrontation with Cawl (calling him a bad father, even while acknowledging the necessity of his sins) is one of the book’s strongest character moments.


Lousy negotiators: Iron Warriors and Vashtorr
The third thread follows Warsmith Kraverek and an Iron Warriors warband who believe they are using Chaos as a tool. Alongside Dark Mechanicum allies, they summon and bind an avatar of Vashtorr the Arkifane, or so they think.
In reality, Vashtorr is the novel’s greatest red herring. He allows himself to be bound, manipulating events from the shadows. He never meets Cawl. Cawl never even knows he exists. And yet, Vashtorr orchestrates much of the catastrophe, using fractions of his Soul Grinder legions to test the pylons and draw Cawl into the open.
Vashtorr the Arkifane, a demigod, emerges as a dark mirror to Cawl: another godlike engineer obsessed with creation, domination, and transcendence. His ultimate goal is not destruction, but acquisition. He wants Cawl (not his soul, but the man himself) as a servant in the Forge of Souls.
The implications are deliciously ominous.


The most important outcome of Archmagos is not the spectacle, but the consequences.
Cawl’s pylon network does three unprecedented things:
1. Allows safer and more stable passage through warp-ravaged space
2. Can permanently close warp rifts
3. Can permanently destroy daemons, not merely banish them
When the pylons activate, Soul Grinders are annihilated forever. Psykers scream, astropaths die, and reality itself recoils but the warp recedes. The Pit of Raukos is not sealed. It is gone. This is not a reset button but a tectonic shift.


For the first time, it is theoretically possible for the Imperium to close the Great Rift. Not easily. Not cheaply. But possible. And that makes Belisarius Cawl the most dangerous and important man in the galaxy perhaps even more than Guilliman himself.

[Jacob L · Rating 2 out of 5]

This book had no substance. It followed tired 40k tropes all to the plot point of Cawl getting Pylons working. There was even a “post-cutscene” of the guys we spent 20% of the novel with saying “my plans go beyond this”. There was a duel between a previously-unheard daemon and named ultramarine. What a wash

[Gary · Rating 4 out of 5]

All praise Belisarius Cawl!

Another great tale featuring our ever so egotistical and accomplished Belisarius cawl, however this time we get to witness him through the eyes of historitor Solana an adept sent by Lord Guilliman to record (spy) on Cawls progress with the Necron Pylons.

For him to achieve this, he needs valuable untouched tech set on a planet that is being consumed by a black hole and thus weird time shenanigans and adventure abound.

Guy Haley is clearly in his element when it comes to Cawl, the character is so magnetic and fun to read that you can tell the author is having a blast with him.

There are other plot lines involving one of which is an iron warrior warband who believe they have shackled one of the most interesting villains to come out of gamesworkshop in recent years and he is called Vashtor. I would arguably say this character was just as fascinating to read as Cawl and I'm very much looking forward to seeing where his storyline goes.

The story is not without faults, the other plotline featuring returning space marine Felix set on the wolfspear planet of Ulviem was completely forgettable and dull mainly because I just wanted to stay with Cawl and his adventure, proof really with how engrossing a storyline Cawls was.

Overall a great Cawl story that concludes with Cawls' typical theatrical flourish.

[Laurence · Rating 2 out of 5]

I'm sad to give this book such a low rating, since the title character of Belisarius Cawl is one of the most fun personalities in the 40k setting. He's on top form in this story, but alas the plot is not worthy of his genius.

There is much padding, with set-pieces that do not serve to advance the plot, including my personal pet peeve of a Chaos ritual overly described. Too often does the viewpoint cut away from our erstwhile protagonist to the machinations of those who work against him, to the benefit of neither side. A more focussed perspective would have aided things immensely.

There's also disappointment generated purely from the blurb on the back cover: anyone looking forward to a meeting of the minds as powerful as when Cawl met Fabius Bile in 'Genefather' will be disappointed, as there is no interaction between the primary rivals this time around! Indeed, Cawl is not even aware of who he is facing or their name!

If your tolerance for the politicking of Chaos Space Marines is greater than mine, perhaps you may find this book more enjoyable. As it is, while Guy Haley continues to write Cawl as a delightful eccentric, there's not nearly enough of him on these pages for my taste.

[Matt TB · Rating 4 out of 5]

Really enjoyed this, great follow up to the Dawn of War series (I think it comes straight after book 9 the Silent King).

The descriptions and imagery of impossible things work well for me, I adore the character of Cawl more with every new book he turns up in.
I loved the perspective of the Historitor too.

The ending seemed to happen a little quickly but drawing it out may have felt off.

Worth it for AdMech, Necron and good ol space marine fans.
Would be worth reading Dark Imperium (possibly the rest of that trilogy), Cawl: the Great Work, as mentioned the Silent King and even though I think it occurs after this Genefather too.

[Kyle Schnyder · Rating 3 out of 5]

This one was my least favorite of the Cawl trilogy. It was carried hard for me just by how much I love Cawl and Felix, but I felt like the plots they both were involved in here were weaker than the previous novels. The quantum tunneling to the planet’s surface was definitely interesting and I liked how Haley described everything that went into making it happen. I just didn’t find the Necrons that interesting nor Cawl’s claiming of the technology he needed, despite that technology being a huge plot development for the wider narrative. Kind of a similar thing with Vashtorr where it’s interesting where his story is going, but it wasn’t all that interesting in this book.

[Gregory Rumeser · Rating 4 out of 5]

A really fun and exciting book. I absolutely love the way Guy Haley has written Cawl as a character and he has the perfect blend of humanity and humor. There are a few parts early on that feel a bit slow but other than that, the book is a thrill ride. The way Vashtor is depicted was really cool as well.

[Pallav · Rating 5 out of 5]

What a fantastic book!! Archmagos Dominus Cawl is a character that's fascinating, impressive and absolutely bonkers. Cawl is someone you want in your corner when everything is going to shit because he will have a plan and he will get you out of the mess. Such a wonderful story. Can't wait for more adventures of the Archmagos.

[Tom Fishwick · Rating 5 out of 5]

A brilliant read. Cawl is an awesome character taking the world of 40K apart. The enemies for the most part are demons and Chaos Space Marines, plus a few Necrons.
He has a voyage into a black hole and through the less hostile environment of the warp.

[Parker Cohen · Rating 5 out of 5]

Overall a fantastic story. Much better than Genefather. Cawl and Solana were great in this book, as was Felix and the machinations of Vashtorr

[Nick Caris · Rating 4 out of 5]

hey verhaal van cawl blijft heerlijk en deze nieuwe editie is een mooie toevoeging daarvan. Een lekker simpel maar leuk avontuur met alle verwachte tech mumbojumbo en overdreven tropes

[Andrew Peel · Rating 3 out of 5]

Good read however far too much padding.

[Phillip Wyrick · Rating 2 out of 5]

The parts with Cawl actually in it were good. The rest, an absolute slog.

[Jesper Karlsson · Rating 5 out of 5]

One of the best books in my 40k collection and Cawl and Haley have both become my favorite characters in the black library.

Haley has the ability to make the characters in his books feel unique and distinct, and he brings out the human, in the inhumane. And even if the relationships he explores can be of a somber matter, he is one of the few black library writers that adds just the right amount of comedic touch.

Cawl is the eleven thousand year old robot-man, who spent ten millennia, trying to bring back his only friend. Be it out of guilt or loneliness and you can really empathize with this, but at the same time he has the narcissists perspective of "I can fix this and make it right, and then everyone will be happy".
He also has the selfish need to feel loved like a father, and an adopted son, that yearns for the love of a father, but they both know that the atrocities commited to place them where they are in life, have both been necessary and makes that relationship impossible.

This has been an other one of the few books I have, where there was no part in the story, where I had to force myself to sit down and read, to get to the good part, we got plenty of things resolved, and an equal amount of new opportunities and open endings, and contrary to the ending of the "dawn of fire" series, now I'm actually happy about it, because I can hope that we can get a few more books with Cawl.

My only concern is if an other writer gets to jump in between it wont be the same, I would claim that its Haley's style of writing that makes this character work.. I wont forgive what they did to my girl Chelche..