Before the Warmaster was ever touched by the Dark Gods, the sons of arid Colchis were already conversing with the shadows. The first disciples of Chaos amongst the Legiones Astartes, the Word Bearers, have been scheming for decades to bring about the ascendance of the Primordial Truth.

Now that the Warmaster is sworn to the Truth, other plans are coming to fruition. While corruption and conversion are in store for many of their fellow Legions, one Legion in particular has drawn their ire and is marked for destruction: the Ultramarines and their primarch, Roboute Guilliman.

Become privy to the origins of Lorgar's faith, walk along with his favorite son on a pilgrimage into hell and stand beside as they strike out for their most hated siblings.

The feud between the Ultramarines and the Word Bearers is, quite literally, the Horus Heresy’s ultimate Team Blue versus Team Red. The Word Bearers are usually short-hand for “evil Chaos worshippers”, the first Legion to willingly embrace Chaos and the breeding ground for the likes of Erebus and Kor Phaeron. The Ultramarines on the other hand are so loyal to the Emperor and the Imperium that the rebels didn’t even consider converting them to their cause and instead directly went for a plan to destroy them. The Ultramarines are reasonable where the Word Bearers are fanatical, logical where their cousins are zealous, driven by a dedication to laws and rules where the sons of Lorgar are driven by belief and passion.

The Omnibus opens up with a short-story, Scions of the Storm, which is about what seems to be a standard compliance action conducted by the Word Bearers during the Great Crusade. Things take a darker turn towards the end, with dark tidings for what might be afoot beneath their veneer of compliance and conformity.

The first novel of the Omnibus, Battle for the Abyss by Ben Counter, also starts off during what seems to be business as usual in the Sol System near the end of the Great Crusade. But then a plan of the seemingly loyal Word Bearers reveals itself to launch a giant ship towards the heart of Ultramar, the home of the Ultramarines. A rag-tag group of Ultramarines, World Eaters, Space Wolves and a Thousand Son race off in pursuit and try to avoid catastrophe. Battle for the Abyss is sort of a prequel to Know No Fear, but is very much a self-contained story. Track of Words wrote a longer article about revisiting the book more than a decade after its release.

After their initial depiction as diabolical, moustache-twirling villains, the novel The First Heretic by Aaron Dembksi-Bowden takes a much more nuanced look at the origins of the Word Bearers’ falling out with the Imperium and their turn towards worship of the Gods of the Warp. Dembski-Bowden brings empathy and care to the depiction of the Word Bearers, especially their primarch Lorgar and the book's main point-of-view character Argel Tal. Their turn towards Chaos is told as a believable tale about searching for answers in the wake of disillusionment and humiliation. It’s an important book to understand the temptation of Chaos and what motivates and drives the Chaos Gods in the first place. To quote 'the Opening Line of the Book of Lorgar, First Canticle of Chaos', from Aurelian: “All I ever wanted was the truth.” I’m freely admitting to being biased here: The First Heretic is probably my favorite Horus Heresy novel. Highly recommended.

This is followed up by another of my personal Top 5 Horus Heresy novels: Know No Fear. Dan Abnett returns for a third time to the series after Horus Rising and Legion to tell the tale of the Battle of Calth, in which the Word Bearers launch a surprise attack on the oblivious Ultramarines. The book is told in the present tense across a vast range of point-of-views, delivering one of the most tense accounts of all-out battle of the whole series. This is the true entry point for the Ultramarines into the civil war and their personal Dropsite Massacre. The Battle of Calth was expanded beyond Know No Fear in several stories, which are collected in the second Shadow Crusade Omnibus, Underworld War (s. below).

The Omnibus is closed off by another short-story, Honour to the Dead by Gav Thorpe. Honour to the Dead was originally produced as an audio drama and later re-published as a short-story. It takes place during the Battle of Calth, where a group of Ultramarines is fighting in the shadow of Titans marching to war. Aaron Dembski-Bowden in an interview once called the “honour to the dead”-line in this story the point that marks the transition of the Space Marines of the 31st millenium into the warriors of the 41st millennium. “I wish I had written that.”. I think it is a fitting closing chapter for an Omnibus that’s all about crossing lines.

Roboute Guilliman: Lord of Ultramar by David Annandale was the first Primarchs-book to be released. It set the basic premise of the series and showed a pre-Heresy Guilliman during the Great Crusade in a campaign against an Ork empire that has him struggle with his Legion's qualities and faults as well as his unique morals and abilities. This isn't required as a prequel to Know No Fear because that novel does a great job a introducing Guilliman and the Ultramarines amidst and through the action taking place, but can be approached as a neat slice of bonus content at a time of your choosing whenever you're eager for more stories about the XIIIth Legion and their primarch.

Lorgar: Bearer of the Word by Gav Thorpe tells the story of Lorgar's upbringing on Colchis. It's told through the eyes of Lorgar's abusive foster-father Kor Phaeron as well as a slave that grows close to Lorgar. It's an interesting addition to The First Heretic because it presents Lorgar through a different lens, which allow for subtle twists on and different readings of his character. Here's Gav Thorpe talking about Bearer of the Word.

As a Phase II Omnibus, this can be read as soon as one is finished with the opening novels. The corruption of the Word Bearers is a cornerstone in the arc of “Chaos as a character” and the Battle of Calth one of the most important battles of the war, so this should be read by any reader of the Heresy.

It’s also one of Omnibuses that directly covers the Dropsite Massacre on Isstvan V, one of the most far-reaching events of the Heresy. If you have, for some reason, skipped Fulgrim, here's your chance to catch up.

The direct sequel to Only the Faithful is Shadow Crusade III: Chosen Of Chaos. Among other things, it tells of Erebus' plan to corrupt the Blood Angels as well as the next steps on Lorgar and Argel Tal's road, this time alongside Angron and the World Eaters. Other characters from this Omnibus are revisited there again, like Sor Talgron from Scions of the Storm.

There are a lot of additional stories about and around the Battle For Calth from Know No Fear, so much so that I decided to bundle them in their own Omnibus: Shadow Crusade II: Underworld War. That Omnibus is a detour that you can take if you're interested in exploring that particular conflict to its fullest. It's optional, though; Know No Fear gives you everything you need to know to continue along to Shadow Crusade III and beyond.

This omnibus is the first of an 'omnibus bundle': *Shadow Crusade I, II & III, Anvil of War* and Angels of Darkness are three narrative threads that together form the “Prelude to Imperium Secundus”. They all eventually converge in and are required prequels to Imperium Secundus I: Hope's Kindling. If you want to eventually proceed to the Imperium Secundus storylines, I recommend reading all or most of these "Preludes" beforehand.

The story of the Salamanders and their primarch Vulkan, who are one of the Legions massacred at Isstvan V, gets expanded upon and continued in Anvil of War.

The story of the Raven Guard and their primarch Corax after Isstvan V gets expanded upon and continued in Shadow of the Warmaster III: Jaws of Defeat.

The story of the third Legion caught in the trap of Isstvan V, the Iron Hands, gets expanded upon and continued in The Truth of Iron.

In general, I’d recommend reading all of the four Phase II Omnibuses (Shadow of the Warmaster I; Shattersong; Shadow Crusade I; The Burning of Prospero) at some point before proceeding into the later Phases, no matter what road you'd like to pursue. All of them cover important events for the series (the flight of the Eisenstein and the formation of the Knights-Errant; the Dropsite Massacre of Isstvan V and its fall-out; the corruption of the Word Bearers and the Battle of Calth; the destruction of Prospero) and introduce characters that will be recurring players all across the series.

Once you've read all of them, you can either proceed to one of their Follow-up omnibuses or jump into one of the Phase III-omnibuses that don't have a direct prequel: Omnissiah I: Death of Innocence, Angels of Darkness or Anvil of War.

Check the Omnibus Map for visual assistance in navigating your options.

The following are recommendations from other series and the wider Black Library canon. If you are interested in the characters, factions or themes that were part this omnibus, the following books might also be to your liking.

Books from the 41st millenium:

• Uriel Ventris series by Graham McNeill, starting with Nightbringer

  • A classic by now, this book series follows the trials and tribulations of Captain Uriel Ventris, who among others clashes regularly with his nemesis, the Iron Warrior Honsou. The series started with Nightbringer (2002) and grew with Swords of Calth (2021) to a number of seven novels, alongside various short stories and a graphic novel. The whole series except Swords of Calth was collected in The Uriel Ventris Chronicles Volume 1 and Volume 2

• The Word Bearers trilogy by Anthony Reynolds, starting with Dark Apostle

  • This trilogy follows a warband of Word Bearers along their road to daemonic ascendance. This trilogy is as dark as it gets and really dives into the monstrousness of Chaos. Some of the Chaos Space Marines from this trilogy appear in cameos alongside the Word Bearers arc in the Horus Heresy stories.