Garro: Oath of Moment

The Horus Heresy #Audio Drama

by James Swallow

In surviving the horrors on board the Eisenstein, Nathaniel Garro proved his courage and absolute loyalty to the Emperor. On his return to Terra, Garro is despatched on a mission of even greater importance – a mission given to him by Malcador the Sigillite himself. He soon finds himself back amongst the stars and on the fields of battle, thrust into a warzone where the Ultramarines are purported to be battling a greenskin invasion. Once again Garro must fight for survival, but now he also fights to achieve a higher purpose...

Genres: Audiobook, Science Fiction, 40k, Fiction, Fantasy, Action, Short Stories

Audio CD

First published December 9, 2010

About the author

James Swallow is a New York Times, Sunday Times and Amazon #1 bestselling author and scriptwriter, a BAFTA nominee, a former journalist and the award-winning writer of over sixty-five books, along with scripts for video games, comics, radio and television.

DARK HORIZON, his latest stand-alone thriller, is out now from Mountain Leopard Press, and OUTLAW, the 6th action-packed Marc Dane novel, is published by Bonnier.

Along with the Marc Dane thrillers, his writing includes, the Sundowners steampunk Westerns and fiction from the worlds of Star Trek, Tom Clancy, 24, Warhammer 40000, Doctor Who, Deus Ex, Stargate, 2000AD and many more.

For information on new releases & more, sign up to the Readers’ Club here: www.bit.ly/JamesSwallow

Visit James's website at http://www.jswallow.com/ for more, including ROUGH AIR, a free eBook novella in the Marc Dane series.

You can also follow James on Bluesky at @jmswallow.bsky.social, Twitter at @jmswallow, Mastodon at @jmswallow@mstdn.social and jmswallow.tumblr.com at Tumblr.

Reviews

[Simon · Rating 1 out of 5]

Blev aldrig færdig med bogen pga underlægnings lydene. Jeg hadede dem med 1000 soles intensitet! 10 min inde, og jeg måtte stoppe.

Et eksempel med tekst fluks hugget fra Mordet i orientexpressen:

“At 1:15 came Mrs. Hubbard's announcement [DAKKA DAKKA!] that there was a man in her room, [BOOOM] who had, for reasons which I dare
not even guess, shed a button [MORE DAKKA DAKKA!] . The next morning, the murder was discovered. [FAZAAAAM!]
Dr. Constantine sets the time of the murder [KABLAAAM!] anywhere between midnight and 2.00 a.m. Now, I came to various conclusions. [KAZEEEEM]”

En konstant kakofoni af dårlige lyde fra det billigste lydbibliotek de har kunnet finde, som nogle gange gjorde det svært, at høre hvad oplæseren sagde.

[Mario Caronna · Rating 5 out of 5]

Garro is one of the best character of Horus heresy series. This audio drama is cool, maybe a little short, 1 hour, but is good. The arrival of Garro is epic.

[D · Rating 4 out of 5]

- Quote: "Your brothers survived. Take that as a reward."
- Thoughts: It's what could be a chapter of a good book, but on itself it does not have deep enough. Ok, this is actually the first part of 3 or something, but it
A too rich and deep (and expensive) setting for such a short story to cause any real impact.
▶◀
These are my personal opinions, you may discord, my final rating of the book is not necessarily linked to this system and may diverge from it.
Book Storyline
- Originality: 3/5 stars
- Development: 4/5 stars
- Enjoyment: 4/5 stars
- Writing stile: 4/5 stars
- Funnyness: 1/5 stars
- Epicness: 3/5 stars
- Scaryness: 1/5 stars
- Smartness: 3/5 stars
- Addictiveness: 2/5 stars
- Plot twists: 1/5 stars
- Pace: 3/5 stars
- Storyline planning: 3/5 stars
- Ending: 3/5 stars
- Holes: 1/5 negative stars
- Self contained (Y/N): ✓
- Cliffhanger (Y/N): ✓
- Adult (Y/N): ×
- Mystery (Y/N): ×
- Treasure Hunting (Y/N): ×
- Violence level: War
- Tech level: Power Armor, Starships
- Religion level: Fictional Religion fanatism
- Main genre: War
- Subgenre: Warhammer 40K
- Point of view: 3
- Best of it: It shows potential
- Worst of it: Very expensive universe
- Aftertaste: Cool
Narration
- Quality: 4/5 stars
- Style: 4/5
- Sound effects ✓
- Multiple voices ✓
- Background music ✓
- In a few words: Exagerated accentuations like old comic books.
World
- Originality: 4/5 stars
- Variety: 4/5 stars
- Consistency: 4/5 stars
- Impact on the story: 2/5 stars
- Maps: -/5 stars
- Real world (Y/N): ×
- Fantasy based on real world (Y/N): ×
- Journey (Y/N): ×
- Main scenario: Civil war in a galactic empire
Characters
No growth, very clichè characters, placed in the right positions.
- Consistency: 4/5 stars
- Connection: 2/5 stars
- Dialogs: 4/5 Stars
- Interactions: 4/5 Stars
- Underworld Crew (✓/×): ×
- Training (✓/×): ×
- Romance: Badass soldiers don't know this word.
Setting
A gargantuan setting, also a very expensive one.
- Setting overall score: 5/5 Stars
- Tension: 2/5 Stars
- Atmosphere: 3/5 Stars
- Geneforge ✓
- Powerarmor ✓
- Psy Powers ✓
Rules
- Devised system: 5/5 stars
- System complexity: 3/5 stars
- System explanation: 2/5 stars
- Impact on storyline: 3/5 stars
- Rulebreaker (Y/N): ×
- Type of Rule: Advanced Tech, Mind Powers

[Joe Coulter · Rating 5 out of 5]

“When all else falls, only duty remains.”

Garro: Oath of Moment is the beginning of a legend born in fire and betrayal. James Swallow delivers a lean, emotionally-charged tale that doesn't just bridge the gap between Horus Rising and Flight of the Eisenstein — it cements Nathaniel Garro as one of the most compelling figures of the Horus Heresy.

This isn’t a story about bolter spam or space marine glory. It’s about a man stripped of everything but his oaths, watching the galaxy collapse around him — and still standing tall. Garro is the Death Guard at his finest: disciplined, unyielding, and defined by loyalty to something higher than any single Legion.

The novella takes place during the Isstvan system’s slow implosion, but it’s quieter, more personal. A conversation with Malcador, a moment of reflection, the forging of a new purpose. It's short — but it's a pivotal spark in the fire that becomes the Knights Errant.

Swallow’s writing is sharp, reverent, and efficient. He knows Garro is a knight out of time — a doomed loyalist in a traitor's skin — and he gives him the weight he deserves.

Verdict: A moment becomes a mission. Garro: Oath of Moment is required reading for anyone who wants to understand why loyalty, in the 31st millennium, is both a curse and a crown.

Recommended for: Loyalist fans, Heresy historians, and anyone who loves watching a true warrior redefine his purpose.

Not for: Readers looking for long-winded lore dumps or massive action scenes — this one is all about character, conviction, and quiet power.

[Martti · Rating 2 out of 5]

There is a whole series of short stories named after the hero of the Eisenstein, Garro. And if there would have been a volume or chapter number on the stories, then "Oath of Moment" would have been number 1. It would have cleared the status of the protagonist for further missions, but when you would have been like me and read them alphabetically, then you reach here probably as the third story and the first ones would mostly be like a bunch of lunacy.

Garro has a secret mission from the Emperor's most trustworthy psyker, Malcador the Sigillite, to gather a super-hero team who for whatever reason cannot be summoned by the usual means of military hierarchy and radio communications. Instead there is a series of stories where Garro personally needs to act all tough and secretive like an idiot instead of just declaring that he has the authority and that's his mission. But I guess simply carrying out orders wouldn't be an interesting read, instead you would witness the military system working as it should. But then you wouldn't have a readon to spend money on Games Workshop products.

I didn't spend on this product specifically, but just trying to get though everything in the Horus Heresy Humblebundle that I got a while back https://www.humblebundle.com/books/ho...

[Jake · Rating 3 out of 5]

This is where the Garro side plot seems to begin, flashing back explaining his Oath of Moment to Malcador. Like many of the Garro audiodramas, this one centers around him recruiting and finding people to join his team towards an undisclosed goal.

Honestly, I didn't find the Ultramarine he was recruiting that interesting. There is a compelling examination of the struggle not to use psychic powers, at the cost of friends' lives, but this didn't call to me as much, mostly because the psycher in question was sort of a flat boring character.

Much more interesting was the beginning of the story, following the battered and stunned imperial guardsmen, struggling to survive the word bearer onslaught.

While this story is important (ish) to establish Garro's actions, the flashbacks break an already short story up too much.

Enjoyable, but not mind blowing.

[RatGrrrl · Rating 5 out of 5]

May 2024 Read using the Horus Heresy Omnibus Project Reading Order (https://www.heresyomnibus.com) as part of my Oath of Moment to complete the Horus Heresy series and extras - Now in Immaterium of everything outside the Horus Heresy Omnibus Project, before moving on to the last Omnibus XXI The Siege of Terra.

This is my first time returning to an audio drama I've listened to many, many times since undertaking this ordeal, having read the 'novel', Garro, during the relevant omnibuses and I had a great time.

This is the first outing of Garro an Agent of Malcador and the first time we see the former Death Guard Battle-Captain since his ordeal on the Eisenstein. It's so first time the title of Knight Errant comes up as an apropos piece of derrision, rather than anything official, as Garro is quite literally the eponymous Legion of One, Qruze not having joining the Sigillite’s order yet.

His first assignment is to recruit Rubio of the Ultramarines, former Codicier and ultimately the first Psyker to join the fledgling host that grows to become only Psykers by the 41st Millennium. Rubio is on Calth in the middle of the march of the Word Bearers and the Ultramarines falling back to the arcologies and has no wish to leave his brothers to die along with Calth...

I do thoroughly enjoy the Garro 'novel', regardless of my mocking of it thinking it isn't an extended anthology, and it's great to have the stories all together with the additions, but coming back to this, I don't know if it's nostalgia or purely in my head, but there's just something different about audio drama Longworth from audiobook Longworth and he's really having fun with it and putting on a show with this.

It's just so much fun. Plus I do find the music and sound effects charming.

The friction with Malcador is great and the tension and tragedy of Rubio's being so desperate to stay with and protect his brothers is what leads them to turn their back on him that quintessential Horus Heresy grimdark bittersweetness I love.

Just a bloody good audio drama and it's impress how good they were from the jump.

I'm genuinely glad that, rather than just listen to the Black Shields audio dramas, I decided to listen through the whole of the Errant Knights collection.

Through the Horus Heresy Omnibus Project and my own additions, I have currently read* all 54 Horus Heresy main series novels (+1 repeat), all 25 novellas (+2 repeats), as well as the Macragge's Honour graphic novel, all 17 Primarchs novels, 3 Characters novels, and 143 short stories/ audio dramas across the Horus Heresy (inc. 10+ repeats). Plus, 2 Warhammer 40K further reading novels and 1 short story...this run, as well as writing 1 short story myself.

I couldn't be more appreciative of the phenomenal work of the Horus Heresy Omnibus Project, which has made this ridiculous endeavour all the better and has inspired me to create and collate a collection of Horus Heresy and Warhammer 40,000 documents and checklists (http://tiny.cc/im00yz). There are now too many items to list here, but there is a contents and explainer document here (http://tiny.cc/nj00yz).

*My tracking consistently proves shoddy, but I'm doing my best

***

Initial Review: 4/5

Following the events of The Flight of the Eisenstein Swallow returns to Garro as he begins his work as Knight Errant for Malcador, the Sigilite, as the Grimdark Ash Ketchum.

If we consider the Lunar Wolf, Iacton Qruze to be Garro's Pikachu, the Ultramarine former Codicier, Tylos Rubio, is a Caterpie, making the blasted hellscape of Calth Viridian Forest.

The story is great. We get a lot of big things for the Heresy, lore, and a bunch of, if not the very first, one of the first fimes we see a lot of new things. We have Garro donning the grey and Malcador's sigii, recognisable as what will become the 'stylised I' of the Inquisition, and starting to catch em all, officially ruled rule breaking (I'm too tired to rant about Nikea, and how it makes no sense with the Emperor and Malcador, but is a cool biblical canon reference), one of the first time we see Chaos Cultists, mutants, and a Daemon engine (Defiler). There a decent bit of action and dialogue.

The writing is quality, Swallow brings his A game to early Heresy and audio dramas, which I continue to be shocked by after struggling through the Rafen Blood Angels books. The production is great. The early and later audio drama production is generally grea, but there as a period in the the middle of the series when things got a little maximalist. Thankfully, this is in an early sweet spot. Toby Longworth handles the narration beautifully and, though I have come to appreciate more of the regular players, he simply is what the Dark Millennium and Space Marines truly sound like to me.

I hate scoring art because it's ridiculous and subjective, and I remember being utterly blown away when I first listened to this many years ago, but I have been going back and forth on whether to give this four or five out of five. I settled on four because I don't do decimal scores and this is right on the entirely arbitrary and made up line between four and five.

Ultimately, this audio drama is Nathaniel Garro, hardworking, diligent, does all the things needed and will skill. It just lacks the character/ emotional connection that I need, which elevates stories like Raven's Flight and After Desh'ea for me. It's still bloody good and I'm excited to listen to the other proto Grey Knights audio dramas I've heard and her on the ones I haven't as I work through the Errant Knights collection

[Ross Cudmore · Rating 4 out of 5]

“When all else falls, only duty remains.”

Nathaniel Garro first introduced in "Flight of the Eisenstein" is a warrior without a purpose, a brother without brotherhood, a son without a father. By remaining loyal to the Emperor he has betrayed his Legion.

Tasked by Malcador the Sigillite to recruit ecruit Rubio of the Ultramarines, former Codicier, Garro will have to fight through the battle of Calth to find and test Rubio. Garro struggles internally as he watches the Imperium collapse from betrayal. A dramatic and engaging tale of loyalty, honour, and duty.

[Travis · Rating 3 out of 5]

Except for the propensity by these guys to not match the background sounds to the narration, this was a pretty good story, and I hope to find more like it, since I seem to have trouble finding ones I really like in this series.

[Gamer Gamersson · Rating 2 out of 5]

Honestly, really boring. I'm not a fan of Ultramarines on the best of days, and I find Rubio to be a pretty unlikable character. Not a fan of his arc in this one, and honestly towards the end of it I found myself skipping ahead more and more.

Garro is the one redeeming factor of this book.

[Patrick Rauland · Rating 4 out of 5]

Introduces Garro as Malcador's knight errant. And also introduces Tylos Rubio.

[Carl Grider · Rating 4 out of 5]

More great 40k old radio style drama!

[Eddy George Eden · Rating 5 out of 5]

Awesome!!!!!!!!!

[Christopher Connell · Rating 5 out of 5]

So continues the adventures of Nathaniel Garro. This story follows Garro’s secret mission to recruit a Psyker into a secret Space Marine Chapter.

[John Legg · Rating 4 out of 5]

Short Audibook but really loved it. Further insight into Nathaniel Garro.

[Lanfear · Rating 5 out of 5]

Mis máximos respetos a Garro, como siempre. La legión de uno, el ángel de la muerte que vuela sólo por toda la eternidad... el caballero gris.

[Michael · Rating 3 out of 5]

So are all the Garro dramas just about finding different homies to party with? This one was pretty good. Not sure how I feel if they're all gonna be like this one and Burden, though.

[Steve · Rating 2 out of 5]

Garro gets instructed to do a mission which involves killing some enemies.

Narration is good, but the dialog is stilted and lacking.

Not awful, but not worth 3 stars either.

[Abhinav · Rating 4 out of 5]

You can read the full review over at my blog

https://shadowhawksshade.wordpress.co...

Shadowhawk reviews the first two Garro audio dramas by James Swallow, Oath of Moment and Legion of One, part of the Horus Heresy series by Black Library.

“Some of the most well-written and highly enjoyable audio dramas, Oath of Moment and Legion of One are among James Swallows’ best work for Black Library.” ~Shadowhawk, The Founding Fields

The two Garro audios were the first Black Library audio dramas I ever listened to. It came after a long, long don’t-care attitude because in that time period, I was pretty indifferent to audio dramas. Basically, I was totally fine with missing out on them, mostly because of the price. But I finally gave in last year in August and bought both Oath of Moment and Legion of One in a single go. James Swallow is one of my favourite authors for Black Library and I was expecting them to be quite good therefore. I was more than surprised to find out that these two are really, really good, especially Legion of One.

I listened to Oath of Moment first of course, since it is the first of the Garro audio dramas. The plot focuses on the on-going battle for Calth, where the Word Bearers have launched a surprise attack on the Ultramarines and the latter are reeling and trying to consolidate and repel the unexpected invasion. The setting of the audio drama is very memorable therefore, as it marks the third biggest Astartes versus Astartes conflict in the history of the Imperium up until that point, the first two being the battles on Isstvan III and later, Isstvan V. Jim has definitely succeeded in creating an atmosphere that is just as epic and memorable as the Betrayal on Isstvan and the Dropsite Massacre.

The really short format prevents him from going in-depth of course but then again, that’s why we got Dan Abnett’s Know No Fear which serves beautifully in explaining all that has happened before the events in Oath of Moment.

The pacing of Oath of Moment is pretty good because the audio keeps you involved from the get go with Garro’s arrival to Calth and all the way to the climactic ending. There is action and dialogue and drama and tension aplenty throughout and Jim never really lets you go. The atmosphere that is created by Jim’s words and Toby Longworth’s excellent voice-acting is simply enjoyable. You are really drawn into the narrative.

[Eulercauchy · Rating 3 out of 5]

Fun little side story.

[Lex · Rating 4 out of 5]

As a continuation of the Horus Heresy series, this audio drama comes right after Flight of the Eisenstein. Here, its Captain, Nathaniel Garro, sets out on a mission by by Malcador the Sigillite. (Oh, I must say, that Sigil-engraving laser thing was really cool...I'm still geeking-out about it) I'll stop spoiling the story there...but the premise is very very interesting.
This is my first chance to find out what the difference is between a WH40k "audio book" and "audio drama". The difference is very noticeable! Having ear-blasting sound effects, and powerful voices add to the already awesome narration (and yes, even the narrator's voice is epic). I am now officially addicted to WH40k audio dramas. Note that this is going to be a short listen, but is worth it in all aspects. Still not a solid fan of Garro, though. I've yet to see in the next book/audio drama if that'll change. \m/

[Tom · Rating 3 out of 5]

I didn't think much of Flight of the Eisenstein, it was a dull entry in the Horus Heresy series and I don't really recall its protagonist Nathanial Garro as being in any way interesting. That said, this mini-sequel was a very good read (well, listen I guess it was a audio book). Garro still isn't the world's most engaging hero but his mission was suitably mysterious and exciting enough to draw me in. Especial since it heavily implies that this is the beginning of the Inquisition and the Grey Knights . A minor nit pick is that the performance of Malcador the Sigillitte sounds like a awful impression of the Emperor from Star Wars.

[Nikolis Asimakis · Rating 4 out of 5]

A short story, direct sequel to The Flight of the Eisenstein and the first audio drama of the series.

I loved it. Toby Longworth, the narrator, is the best of the three I've heard as of yet. Also, constant music, battle sounds etc make this an awesome experience.

The story is solid and we see the start of a new unit in the Imperium, with Garro as its head.

The only reason I give this 4/5 is that I did not know that it was a short story and was frustrated when I realised it had ended. This would not be a matter in the sequel, though.

[Alex Jones · Rating 4 out of 5]

This was an excellent, albeit short, audio drama set during the Horus Heresy in the Warhammer 40,000 universe. It is short and self-contained, but exceptionally well put together. The narrator is fantastic, every sentence is said with such relish and excitement, and the voices and music and sound effects added to this very well. My main complaint is that whilst it had great writing, enjoyable plot, likeable characters, etc. is how short it was. At only a bit over an hour, it was over almost before it began and I would have loved for more. Still, certainly a great production.

[Nick · Rating 2 out of 5]

A simple novella about Garro convincing an Ultramarine psyker (or more like coercing, really) to betray the orders of his primarch and join him as a Knight Errant. Not exactly a feel-good story, but it's got some fun bolter porn.

This was also the book that kinda demonstrated the distinction for me between an audio drama and an audiobook. Coming directly from Flight of the Eisenstein, the difference was immediately apparent; there were way more effects and ambient sounds, it was a more all around immersive production compared to just being a narration.

[Jimmy · Rating 4 out of 5]

Short and sweet.
Some decent voice work and sound effects enhance this short story.
For all the people who wanted to know what happened Garro after arriving to Terra, this is, I would guess the first of many short stories telling the tale of his mission from the Siglite.

It ties a few threads together from other recent books in this case providing a good view into the impact of the Council of Nikiela from a standpoint outside of that covered in thousand sons and Prospero burns

Worth a listen

[Dylan Murphy · Rating 4 out of 5]

A good little audio drama. It was really awesome to get to see Garro again, and see him start his quest. I really look forward to seeing where this goes.
That said, the battle scenes were intense, and it was nice getting to see a more human side to the Ultramarines. Garro is as amazing a character as always.

The one thing I didn't like was Malcador's voice. I liked it much better in The Lightning Tower, and I really hope they change voice actors for him in the next ones

[Fabian Scherschel · Rating 5 out of 5]

Once again, James Swallow delivers the goods. The first audio book from him that I've listened to and I am not disappointed. No doubt the beginning of an epic quest for Garro as he enacts the orders of Malcador The Sigillite. Very well written and performed and perfect in length. Everything an audio book and a short story should be. Can't wait to listen to the next one!

[Kjell · Rating 3 out of 5]

Audio book from Black Library, I've started to like the style of these books, about the Horus Heresy Wars. This one feels like a undisclosed chapter in the middle of a good book. I find Mr. Longworth interpretations of space marines voices very good. I hope to hear more of these in the future.

[C.P. Sennett · Rating 5 out of 5]

A very good character emerging in this set.

I like Garro, he is a good character caught up in things well beyond him. The story is good, you emphasise for this poor guy and it is well read with good sound effects.

Well worth getting.