The Horus Heresy (novels)


The Horus Heresy is an ongoing series of science fantasy set in the fictional Warhammer 40,000 setting of tabletop miniatures wargame company Games Workshop. Penned by several authors, the series takes place during the Horus Heresy, a fictional galaxy-spanning civil war occurring 10,000 years prior to the far future of Warhammer 40,000. The war is described as a major contributing factor to the game's dystopian environment.
The books are published in [|several media] by the Black Library, a Games Workshop division, with the first title released in April 2006; as of 2019 the series consists of 56 [|published volumes], with more in the pipeline.
The series has developed into a distinct and successful product line for the Black Library; titles [|have often appeared] in bestseller lists, and overall the work has received [|critical approval despite reservations]. It is an established, definitive component of Games Workshop's Horus Heresy sub-brand, and authoritative source material for the entire Warhammer shared universe and its continuing development.

Overview

The Horus Heresy is a dark, far future military space opera concerning an intergalactic civil war within the nascent Imperium of Man, and which constitutes a cornerstone event of the dystopian science fantasy Warhammer 40,000 universe. The Horus Heresy is presented as a major chapter of conflict in the Warhammer 40,000 lore: it is caused by a [|Chaos] plot to foil the Imperium's leader and founder, the mysterious [|Emperor] of Man, by fomenting rebellion and internecine warfare in the expanding Imperium of Man. The story focuses on the Emperor's 21 genetically engineered lieutenants, the Primarchs, and the legions of genetically-enhanced superhuman soldiers that they lead, the Legiones Astartes, which find themselves divided into loyalist and traitor factions as they struggle for religious hegemony.
The shared universe was originally created in 1987 by Games Workshop, parent company of series publisher Black Library, as the campaign setting for the Warhammer 40,000 tabletop miniatures wargame and in 2006 Black Library began publishing The Horus Heresy series. The series consists of full-length novels, and novel-length compilations of novellas or short stories, written by [|a number of authors]. The series includes new characters as well as establishing the background of previously-established Warhammer 40,000 characters who play an important role in the post-Heresy fictional universe.
The first three novels in The Horus Heresy are an [|opening book trilogy]. This trilogy presents some of the background and causes of the Heresy, and describes the start of the conflict. The arc's focus is on [|Warmaster Horus], the principal antagonist, and covers about two years in the overall Heresy timeline; most of this period elapses before the rebellion begins. Following the trilogy, the narrative is not strictly sequential and is often presented in nonlinear fashion from book to book. Apart from the initial trilogy, the stories often concern events that happen earlier or later than their position in the series would suggest, or may include time periods already covered in other series titles.
The majority of stories in The Horus Heresy are set around the start of the fictional universe's 31st millennium, in contrast to most Warhammer 40,000 material, which takes place in the 41st millennium. The stories in The Horus Heresy routinely cover the conflict's background, with some going back centuries before the war begins. In narrower scope, the entire conflict, is depicted as having lasted less than a decade. With few exceptions, the sequence and dating of Heresy events is implied rather than stated in The Horus Heresy stories.

Titles

The following lists pertain to regular or general-availability UK first editions. For special and other editions, and additional information, see § [|Media and editions].
BookTitleAuthorRelease dateLength

Contributors

Contributors of the series include artists, audiobook narrators, and compilation or abridgement editors. Each may have contributed in stories that utilise different forms; where applicable, the number of contributions per form or other pertinent information is indicated in parentheses.
Artists
Audiobook narrators
Editors

Story setting

Early in the 31st millennium, the Galaxy is in the throes of the Great Crusade. Originating from Terra, it is an interstellar that claims the galaxy as the rightful domain of Humankind, and aims to reunite the multitude of scattered human colonies remaining from earlier space exploration under the domain of an "Imperium of Man". Organised in numerous expeditions, the Crusade fields huge fleets and vast armies; at its forefront, led by the Primarchs, are Legions of Space Marines genetically-enhanced supersoldiers numbering in the millions. Over the course of two Terran centuries, the Crusade has reached star systems more than 50,000 light years away from its original staging point in the Sol System, has assimilated millions of worlds into the Imperium, and has given Humankind a dominant position among the galaxy's species. Its grand mastermind is the "Emperor of Mankind", a mysterious superhuman of unknown origin.
The Emperor, founder and head of the Imperium, is a being of towering charisma, prowess, conviction, and ability. He has declared an agnostic worldview, the "Imperial Truth", which promotes science, rationalism, and human primacy. Unknown to the common citizenry, he is also the most powerful human psychic, referred to as psykers, and is overall one of the most formidable psychics in the galaxy. Officially, the Imperium denies the existence of psychic phenomena, including its manifestations as witchcraft and sorcery, and punishes its belief as ignorant and superstitious; yet the Imperium is also dependent on psychic activity in order to achieve faster-than-light travel between its scattered dominions. The Emperor knows that psychic phenomena originate in The [|Warp], a parallel dimension reflecting the events of the material world at its most emotional. Within the Warp exist Daemons, sentient vortices of concentrated feeling that are chiefly malignant. The Daemons are themselves in service to the Chaos Gods, also known as the Ruinous Powers, titanic collectives of dark will whose rulership over the parallel dimension is supreme. These malign immaterial entities forever seek to breach the material universe and subject all life within it to foul and debased whims. Awareness and perception of the Chaos Gods and their Daemons serves as the basis of numerous faiths and religions in the setting, both human and alien in origin. Knowing followers of the Chaos Gods, though rare, refer to their faith as the [|Primordial Truth], or the Primordial Annihilator.
Humankind's continuing biological and psycho-spiritual evolution includes the gradual development of widespread Warp-related psychic abilities that will make the species far more susceptible to Chaotic influence; united under the Imperium of Man, the Emperor seeks to protect all of mankind by using faith in the [|Imperial Truth] as a shield. The powers of Chaos desire change and conflict by nature, and seek to destabilise and subvert the Imperium's order over the galaxy from within.

[|Book 1] to Book 10

1. Horus Rising: The seeds of heresy are sown
Horus Rising, the series opener, starts in the early years of the 31st millennium, during the 203rd year of the Great Crusade. It describes the rise to power of Horus Lupercal, Primarch of the "Luna Wolves" [|Legion] of Space Marines, and the most versatile and favoured "son" of the Emperor. The Emperor has recently appointed him [|Warmaster], overall commander of Imperial military forces, while also leaving him in charge of the rest of the Crusade; the Emperor meanwhile returns to Terra, where in relative isolation he undertakes a secret project to which not even Horus is privy. The focus and perspective of the novel centres on a Space Marine Captain, Garviel Loken, leader of the Luna Wolves' 10th Company. He becomes a member of the Mournival, an informal advisory body to Horus, and participates in Crusade campaigns against anti-Imperial human populations and aliens, referred to in the series as "xenos". The story also hints at tensions in the nascent Imperium, exacerbated by the Emperor's absence and contentious actions and inactions these are common themes in following books.
2. False Gods: The heresy takes root
False Gods picks up a few weeks after the conclusion of Horus Rising in the series timeline, and tells the story of Horus' fall. In a complicated conspiracy implemented by followers of Chaos, Horus is mortally wounded during a Crusade mission by a Chaos-tainted xenos weapon. In a desperate action by his lieutenants to ensure his survival one taken in strict contradiction to [|Imperial doctrine] Horus is brought to a local temple with a reputation for healing. The temple is the seat of a powerful Chaos cult, and both Horus' wound and its supposed healing makes him susceptible to Chaos' influence. He ultimately turns against his "father", the Emperor, and sets in motion the entire Heresy. This novel further highlights the institutional and personal tensions that accompany the Imperium's maturity into the preeminent power of the galaxy; they include rifts among the Primarchs, as well as both between and within their Space Marine Legions. Conflicts and characters flaws are repeatedly and effectively manipulated by Chaos in pursuit of their agenda throughout the series. A parallel storyline, also present in several other books, involves the growing influence both within the Crusade Expeditionary forces and across the wider Imperium of a forbidden religious cult, whose members, while loyal to the Emperor and Imperium, defy the Imperial Truth by worshipping the Emperor as a god.
3. Galaxy in Flames: The heresy revealed
Galaxy in Flames starts shortly after the end of False Gods. It outlines the corrupted Warmaster's descent into madness, which leads to the fomentation of his plot to betray the Imperium. Horus pursues his secret planning of the rebellion in earnest, seeking and finding allies among his disgruntled fellow Primarchs, their Legions, and the Imperium's other organisations and key personalities. The novel details the first open move of the Heresy, the "Betrayal of Istvaan III", wherein factions of four Astartes Legions who were deemed unconvertible by their traitor brethren are ambushed during a planetary invasion of the fictional star system. The novel marks the first distinguishment of the "Loyalists" and "Traitor" factions within the Legions and other rebel forces, including the unmodified soldiers of the Imperial Army.
4. The Flight of the Eisenstein: The heresy unfolds
The Flight of the Eisenstein follows the eponymous Eisenstein, a space frigate of the "Death Guard" 14th Legion of Space Marines. The story follows the ship's escape from the Betrayal of Istvaan III, crewed by surviving loyalists of the four Legions present at the battle and commanded by Battle‑Captain [|Nathaniel Garro] of the Death Guard 7th Company and one of the few Commanders in the Traitor Legions that remain loyal to the Emperor followed by the perilous voyage the vessel must take across the galaxy in an effort to reach Terra and raise the alarm over the developing rebellion. Garro and the others on board the vessel face suspicion and incredulity from Imperial authorities; apart from the inconceivable news of Horus' betrayal, the situation is complicated by the fact that many of the travellers on the Eisenstein now openly proclaim their belief in the Emperor's divinity, itself a heresy.
5. Fulgrim: Visions of Treachery
Fulgrim centers on the Primarch of the "Emperor's Children". Characterised as flamboyant perfectionists, the novel tracks the descent of Fulgrim and his Legion into the service of Chaos roughly simultaneously with that of time Horus in. Fulgrim is delivered a warning about Horus' imminent betrayal and the disaster that may follow [|by the alien Eldar race], but he and his staff dismiss it. The Emperor's Children eventually become the "Chosen" of Slaanesh, one of the four Gods of Chaos, with which Fulgrim is slowly and unwittingly drawn into grotesque communion. Primarch [|Ferrus Manus] and his "Iron Hands" Space Marines also play a prominent role in the novel as Fulgrim attempts to lure them into betrayal, and several other Primarchs and Legions make appearances. Described in passing is the pivotal Battle of Isstvaan V, also known as the, where several entirely Loyalist Legions are slaughtered in another Traitor ambush in the [|Isstvan star system]. The battle fully reveals the scale and ferocity of the rebellion.
6. Descent of Angels: Loyalty and honour
Descent of Angels is a pre-Heresy story that concludes about 50 years before the start of that conflict. It introduces the "Dark Angels", first of the Space Marine Legions, and their Primarch [|Lion El'Jonson]. The story is mainly told from the viewpoint of [|Zahariel El'Zurias], a native of the fictional planet. [|Caliban] is an isolated, low-technology world that resembles a feudal medieval fantasy setting. Zahariel is introduced in the story as an Aspirant of the Order, an organisation of techno-barbarian knights. The first half of the novel is set on Caliban and covers the final battles of the Order under the leadership of Jonson, the future Primarch. The book's second half describes Caliban's unification with the Imperium of Man as well as the actions of the Dark Angels during the early years of the Great Crusade. In this part of the story, Zahariel, selected as a candidate Space Marine, is accepted as a Dark Angel. A future within the Legion is intimated towards the end of the book.
7. Legion: Secrets and lies
Legion focuses on the "Alpha Legion", the of the Space Marine Legions. Characterised in earlier publications as clandestine and inscrutable, the book constitutes a major development of the entire canon of the setting with the revelation that the Legion's Primarch is actually a pair of twins, [|Alpharius and Omegon]. The book also features the Imperial Army, the regular unmodified human fighting force of the Imperium, covering several officers and their units. Lastly, the novel introduces a new organisation to the setting, the enigmatic and ancient an interspecies organisation opposed to Chaos. The human [|John Grammaticus] is introduced as a prominent Cabal member. The story takes place over roughly a 6‑month period, about two years before the Heresy starts; it describes the events that eventually lead Alpharius and Omegon to support Horus.
8. Battle for the Abyss: My brother, my enemy
Battle for the [|Abyss] concerns the lead‑up to a Traitor invasion of, a remote star system and the home base of the unshakeably-Loyalist 13th Legion, the "Ultramarines". Early in the Heresy, the Traitor Word Bearers Legion is tasked with organising and leading the invasion; they plan to use an immense, secretly commissioned warship, the, to spearhead the surprise attack. The vessel, commanded by Fleet Captain [|Zadkiel], launches from shipyards near Jupiter around the time of the events on Isstvan III, and sets course for Macragge, Ultramar's capital world. Leading the cast of Loyalist protagonists is [|Cestus], Fleet Commander and Captain of the 7th Company of the Ultramarines. They become aware of the powerful capital ship's true purpose, and engage in long pursuit; they will seek to prevent the Furious Abyss from participating in the invasion and from reaching Macragge.
9. Mechanicum: Knowledge is power
Mechanicum is the first book in the series not to focus on either the Primarchs or their Space Marines Legions. The novel centres on the eponymous "Mechanicum", a cult of machine-worshipping technologists based on the real-life planet Mars and which serves as the chief engineering authority in the nascent Imperium. The machinations of Horus and the Chaos-worshipping Traitors affects the Martian cult as much as every other Imperial organisation, leading to a civil war on Mars itself. [|Kelbor-Hal], Fabricator General of Mars and the technocracy's supreme leader, declares for Horus, and together they carry out a coup d'état to eliminate Techpriest and Magos adherents of the Cult who are loyal to Terra and the Emperor. As the Mechanicum is the sole power responsible for all civil and military technology in the Imperium, the conflict has vast implications for whichever side of the broader intergalactic civil war receives Mars' crucial support.
10. Tales of Heresy
Tales of Heresy is a collection of short stories introducing and expanding upon numerous threads within the greater happenings of the Heresy. Various stories centre on the, the elite Praetorian Guard-esque retinue of the Emperor, and the, a classified Imperial organisation of anti-psychic warrior‑nuns originally introduced in [|Book 4]. Most stories are concurrent with the Heresy, with some occurring in the years prior. It includes two stories that take place on Terra, one of which occurs long before the Heresy and adds to the background regarding the Imperial Truth; another entry in the compilation is [|a Primarch] origin story, covering the contentious circumstances under which the gladiatorial Primarch [|Angron] takes command of the, which he renames from the "Warhounds" to the "World Eaters". The book contains seven stories by various authors; several stories relate to full-length novels in the series.
This anthology contains the following stories: Blood Games by Dan Abnett, Wolf at the Door by Mike Lee, Scions of the Storm by Anthony Reynolds, The Voice by James Swallow, Call of the Lion by Gav Thorpe, The Last Church by Graham McNeill and After Desh'ea by Matthew Farrer.

Book 11 to Book [|20]

11. Fallen Angels: Deceit and betrayal
Fallen Angels continues the Dark Angels tale begun in Book 6, Descent of Angels. The novel starts around the time of Book 6's conclusion, about 50 years before the Heresy, but forwards to just about the time of the Heresy's beginning in the opening chapters. It tells two stories: one concerns the effort of Primarch Lion El'Jonson and a small group of Dark Angels to deny a to Horus' forces; the other is the story of Luther, Zahariel El'Zurias, and a Dark Angels contingent sent back to Caliban, the Dark Angels Legion home world. They get involved in the fight against a growing insurgency that seeks to free the planet from under the Imperium's thumb.
12. A Thousand Sons: All is dust...
A Thousand Sons is the story of Primarch [|Magnus] and the "Thousand Sons" Space Marines, the 15th Legion; it mainly takes place before the Heresy begins. Following a reprimand by the Emperor for dabbling in sorcery, Magnus and his Legion secretly continue to study the forbidden subjects. Then, around the time of Horus' corruption, Magnus learns through sorcery of his brother's impending betrayal. He tries again through sorcery to warn the Emperor, believing that the gravity of the news justifies his disobedience. However, he overreaches with his powers and damages the vital and secret project the Emperor is undertaking, endangering the safety of Terra itself in the process. The Emperor is enraged and orders [|Leman Russ], Primarch of the 6th Legion, to, the Thousand Sons Legion's in‑series home world. The Space Wolves, accompanied by other Imperial forces, are to bring Magnus and his Legion to Terra to account for themselves.
13. Nemesis: War within the shadows
Nemesis is set about two years after the events on Isstvan V described in [|Book 5], Fulgrim. It is a look at the war behind the war, the covert operations undertaken by the opposing sides in order to influence the visible conflict. Specifically, it deals with a plan by a secret Imperial organisation, the, to eliminate Horus; an "Execution Force" consisting of operatives from all of the Officio's disciplines, and led by top-rated sniper [|Eristede Kell], is tasked with the mission. There have been several previous unsuccessful attempts against Horus' life, and this gives [|a high-ranking officer] of the Traitor Word Bearers Legion the idea to field a weapon of his own: a highly specialised assassin, who is to be used in an audacious scheme to kill the Emperor.
14. The First Heretic: Fall to Chaos
The First Heretic details the fall to Chaos of Primarch [|Lorgar] and the the "Word Bearers". Decades before the start of the rebellion they become heretics relative to the Imperial Truth by introducing religious worship. This results in public and humiliating censure of Lorgar and the entire assembled Legion, by the Emperor himself. The despairing Lorgar is subsequently swayed by two of his most trusted lieutenants, who are in secret allegiance with Chaos; eventually both Primarch and Legion covertly embrace the Primordial Truth, many years before Horus' corruption. The story is largely told from the point of view of [|Argel Tal], a Captain of the Word Bearers, who becomes commander of a Chaos-possessed elite Legion unit. It spans several decades, starting 43 years before the events on Isstvan V and concluding around the time the Word Bearers are on their way to assault Calth.
15. [|Prospero] Burns: The Wolves unleashed
Prospero Burns is part of the story arc of [|Book 12], however it follows a different but related timeline. The story begins more than a century before the Space Wolves-led mission to Prospero, and the concurrent start of the Heresy. It is presented from the point of view of [|Kasper Hawser], formerly a noted Terran academic who becomes a [|Crusade Remembrancer], and then the Oral Historian or attached to the Ultramarines Legion. He unwittingly becomes the keeper of a secret that could decide the victor in the developing galactic civil war. The secret has additional implications regarding the Heresy's conclusion and the future course of the Imperium of Man. "The Outcast Dead" are other protagonists: a small, disparate group of Space Marines suspected as traitors, with whom Zulane falls in during the second half of the book.
18. Deliverance Lost: Ghosts of Terra
Deliverance Lost is mainly concerned with the actions of Primarch [|Corvus Corax] and his Space Marine Command, or "Raven Guard", during the year following the [|Dropsite Massacre]. However, operatives and the [|Primarch of the Alpha Legion] play a prominent role. The story starts about 3 months after the Dropsite Massacre, with the unexpected rescue of Corax and the remnants of his Legion. Arriving at Terra a few months after the events described in The Outcast Dead take place, Corax convinces the Emperor to impart to him the knowledge and material that may accelerate the rebuilding of his Legion. The second part of the novel describes the effort to reconstitute the Raven Guard, undertaken on , and the pursuit of opposite objectives by the Alpha Legion. The novel features the reappearance of [|The Cabal], and of other well-known characters; it also adds information about the developing strategies and subterfuge applied by the opposing sides, including reasons for Horus' timetable and for the Emperor's actions during the initial stages of the Heresy.
[|19]. Know No Fear: The battle of Calth
Know No Fear documents the rebels' surprise assault on Calth, an ascendant [|Ultramar system] world. It is planned and led by the Traitor Word Bearers Legion, now fully and openly committed to the spread of the Primordial Truth. The narrative starts close to where the timelines of [|Book 8] and [|Book 14] converge, with the invasion force en route to, or near the planet. The rebel mission [|has aims beyond] just delivering a crippling blow to the Ultramarines Legion and their home system; its objectives may affect the entire Heresy campaign. The story tracks the Calth assault from its opening covert phases, and the actions of several characters. Unaware of the developing rebellion and the Word Bearers' true role and allegiance, Primarch [|Roboute Guilliman] and his Ultramarines are unprepared for the underhand invasion: it is total, bloody war, with ritualistic undertones, scorched earth tactics, decisive use of technology, and the considerable involvement of Chaos; the inconceivable treachery and its implications forever change the Loyalists' view of reality.
20. The Primarchs
The Primarchs is a compilation of four novellas by different authors, each story starring one of the [|"sons"] of the Emperor. The novellas further develop these characters, who make multiple appearances in the series: following the Dropsite Massacre, Fulgrim, perversely empowered by his own corruption, reveals his true nature and future plans to top officers of his compromised Legion; during a Great Crusade campaign against the enigmatic Eldar, Ferrus Manus, already beset by unsettling dreams, is subjected by alien sorcerers to stark, portentous visions and warnings about his future and role in the soon to be revealed Heresy; with Horus' rebellion in full swing after [|the events of Isstvan V], a suspicious and isolated Lion El'Jonson accepts the newly revealed realities of the Warp and decides on an independent course of action for the Dark Angels in the unfolding conflict; around the same time, and plotting a typically indecipherable course in the expanding war, [|the twinned Primarch] of the Alpha Legion is involved in a unique counterintelligence operation that extends the Legion's customary deceptions inwards.
This anthology contains the following stories: The Reflection Crack’d by Graham McNeill, Feat of Iron by Nick Kyme, The Lion by Gav Thorpe and The Serpent Beneath by Rob Sanders.

Book 21 to Book 30

21. Fear to Tread: The angel falls
Fear to Tread describes an operation by the forces of Chaos that is supposed to turn Primarch [|Sanguinius] and the the "Blood Angels", to their cause. To succeed, Chaos plans to take advantage of a genetic flaw in Sanguinius' and the Legion's DNA. As the Heresy is getting under way, the outwardly still loyal Warmaster orders the entire 9th Legion and their unsuspecting Primarch to a remote star system. There they find themselves isolated and ambushed, fighting a new kind of war against [|Chaos entities] and daemons designed to trigger the Legion's flaw. The plan almost succeeds; yet conflicting agendas among anti-Imperial protagonists, as well as the fortitude and unorthodox tactics of quick-to-adapt Blood Angels, narrowly result in Loyalist victory. In the meantime Horus' rebellion erupts openly and the Loyalists suffer catastrophic losses in the Dropsite Massacre. Sanguinius and his Legion, now fully aware of the great betrayal and the reality of Chaos, race to the defense of Terra and the Emperor while buffeted by unprecedented navigational difficulties; it is hinted that these are related to the action in the Ultramar system of Calth.
[|22]. Shadows of Treachery
Shadows of Treachery is a compilation that collects five short stories previously published in limited editions, art books, or other formats, and also contains two new novellas. Most of the stories involve the respectively the Loyalist "Imperial Fists" and Traitor "Night Lords", and their Primarchs [|Rogal Dorn] and [|Konrad Curze]. Other Legions and Primarchs are also featured, while one short story takes place on Mars and illuminates an aspect of the [|Traitor Mechanicum's conspiracy]. One of the novellas is mainly about an all-out close-quarters space battle, between a Loyalist sent to punish Horus following the events of Isstvan III and the Traitor fleet that ambushes it; the other new novella deals with the aftermath of another naval engagement in space that cripples the Night Lords Legion. The narratives of all stories fill gaps in the series or add further details about the Heresy and its actors; they cover periods that range from several decades before the conflict to around the time frame of [|Book 18].
This anthology contains the following stories: The Crimson Fist by John French, The Dark King by Graham McNeill, The Lightning Tower by Dan Abnett, The Kaban Project by Graham McNeill, Raven's Flight by Gav Thorpe, Death of a Silversmith by Graham McNeill and Prince of Crows by Aaron Dembski-Bowden.
23. Angel Exterminatus: Flesh and iron
Angel Exterminatus covers a Traitor operation in uncharted and dangerous galactic space, that may purportedly decide the war in favour of the rebels. The story provides further glimpses of disparate motivations and conflicting objectives among traitor factions as the Heresy campaign continues. It is taking place some time after the Dropsite Massacre, shortly following the events described by two novellas. Featured are the 4th Legion of Space Marines, the "Iron Warriors", renowned siege masters of the Great Crusade, and their Primarch [|Perturabo]. However the core plot is set in motion by Fulgrim and the Emperor's Children, who share the spotlight. The embittered Iron Warriors have aligned with Horus out of frustration with the ignominious and unheralded role assigned them by the Imperium; before the story begins, they lash out in unforgivable genocide. In the story, they are invited to the freelance operation by Fulgrim and his Legion, who have their own agenda. The operation's true goal is kept secret from Perturabo and his Space Marines, who come to realise that not all fellow rebels can be trusted. A side thread involves [|Fabius Bile], the chief medical officer of the Emperor's Children, and the Traitors' top geneticist; he is on a no-holds-barred quest to exceed the Emperor's genetic achievements.
[|24]. Betrayer: Blood for the Blood God
Betrayer returns the series to the action in the [|Ultramar theatre]; it starts around the time the events of [|Book 19] begin to unfold. Unlike that story, Betrayer is presented from the perspective of the rebels, in this case the World Eaters and Word Bearers Legions, and often through the particular viewpoint of [|Khârn], Captain of the 8th Company of the World Eaters and Equerry to Primarch Angron. In tenuous and fragile cooperation, the two very different Traitor Legions lay waste to worlds across Ultramar; it is a "Shadow Crusade" meticulously planned by Primarch Lorgar of the Word Bearers, who deploys Abyss-class spaceships. The campaign's strategic goal is the destruction or isolation of the powerful Ultramarines Legion, its home star system, and the system's considerable resources; removing Ultramar as a factor in the war is one of Horus' primary objectives. The scheming Primarch of the Word Bearers orchestrates genocide in unprecedented scale, as a way to summon the powers of Chaos. With their help, he hopes to generate the so-called, an immense interdimensional disturbance that will create an impenetrable veil around Ultramar. As the final piece of his plan, Lorgar engineers the "ascension" into daemonhood of the increasingly unstable Angron: the event is to act as the conduit for the unnatural storm.
25. Mark of Calth
Mark of Calth is the fifth compilation to appear in the series; it contains seven short stories and one novella, each by a different author. The stories further describe aspects of the rebels' Ultramar campaign, as close prequels or sequels of Books 19 and 24. "Premium" editions and the e‑audiobook version were released April 2013; text-based general release editions were expected mid-to-late 2013.
This anthology contains the following stories: The Shards of Erebus by Guy Haley, Calth That Was by Graham McNeill, Dark Heart by Anthony Reynolds, The Traveller by David Annandale, A Deeper Darkness by Rob Sanders, The Underworld War by Aaron Dembski-Bowden and Unmarked by Dan Abnett.
26. Vulkan Lives: Unto the Anvil
Vulkan Lives is the first book where the story of Vulkan is shown with a significant background. His memories coming back to him after his capture by his brother Konrad Curze aboard his ship modified by Perturabo himself. He learns more about his immortality, which seems to be a gift and a curse, one he preferred not to bear at all. The book adds more background concerning the battle at Istvaan V, at the same time showing the drama of a squad of his surviving sons and the shattered legions while they fight to retrieve an unknown artifact that will change the course of history in the coming days of the rebellion.
27. The Unremembered Empire: A light in the darkness
Unremembered Empire happens after the events of the Battle of Phall, the Lion's capture of Konrad Curze, the return of Guilliman to Maccragge after the battle for Armatura and the Blood Angels trial at the battle for Signus Prime. An ancient device has been found on Sotha, one which could guide the mighty warships out of the impenetrable veil that cut off Ultramar from the rest of the Imperium. Strange events start to happen after the arrival of members of the Cabal organization; a Word Bearer Legionnaire seeking redemption for his Legion and the Night Lords' Primarch begin their search for an unknown "object" that fell from orbit straight to the hands of Guilliman. Secrecy between him and the Lion might bring undesired conflict between the brothers in this time of treachery, while Sanguinius manage to come back from his trial on Signus Cluster to learn from Guilliman's plan for a new Empire.
28. Scars: A Legion divided
29. Vengeful Spirit: The Battle of Molech
30. The Damnation of Pythos: Thinning the veil

Book 31 to Book 40

31. Legacies of Betrayal: Let the galaxy burn
32. Deathfire: Into the Ruinstorm
33. War Without End: Heresy begets retribution
34. Pharos: The dying of the light
35. Eye of Terra: I am the Emperor's vigilance
36. The Path of Heaven: Riding Out from the Storm
37. The Silent War: Chosen of the Sigillite
38. Angels of Caliban: Emperors and slaves
39. Praetorian of Dorn: Alpha to omega
40. Corax: Nevermore

Book 41 to Book 54

41. The Master of Mankind: War in the webway
42. Garro: Weapon of fate
43. Shattered Legions
44. The Crimson King: A soul divided
45. Tallarn: War for a dead world
46. Ruinstorm: Destiny unwritten...
47. Old Earth: To the Gates of Terra
Old Earth tells the story of the newly resurrected Vulkan, who is compelled to leave his homeworld and his legion behind and return to fulfill his destiny at Terra. To break through the ruinstorm, which is keeping the throneworld inaccessible via the warp, he must make use of ancient Eldar pathways, where humans are not welcome. En route he seeks aid from Shadrak Meduson and the Iron Tenth, who continue to harass the traitorous Sons of Horus with guerrilla tactics. But Shadrak is facing internal resistance to his attempts to revitalise the Iron Hands, while at the same time seeking a showdown with his nemesis Tybalt Marr.
48. The Burden of Loyalty
49. Wolfsbane: The wyrd spear cast
50. Born of Flame: The Hammer and the Anvil
51. Slaves to Darkness: Chaos undivided
52. Heralds of the Siege
53. Titandeath: The God Machines cometh
54. Buried Dagger: Doom of the Death Guard

Book 55 onwards: ''Siege of Terra''

55. The Solar War
56. The Lost and the Damned
57. The First Wall
58. Saturnine

Media and editions

Series titles are released in multiple versions: in print as paperbacks and hardcovers ; as e-books; and as either abridged or unabridged audiobooks and e‑audiobooks.
, print editions were generally though some mass market versions have rendered in more; total series length in first paperback edition was about . Digital editions ranged in size from less than a megabyte to over a gigabyte ; the totals run from a low of about 10 MB to a high of about 11 GB. Durations of audio versions spread from about 6 hours for the abridged editions to anywhere between for the unabridged editions; the total length of the unabridged edition was about 168 hours, divided among 13 titles. CD audiobooks were published in packages of 5 discs per abridged title; two unabridged titles were available on CD, with the longest packaged in 13 discs.
Outside the UK, series titles are published in several countries and languages by Black Library divisions or as co-editions with local associates., other-language renditions lagged the English-language series in the number of released titles, and had followed distinct publication schedules and release sequences. Also as of 2013, editions in other languages were published in paperback and e‑book formats.
Starting November 2010, new titles have often been released simultaneously in multiple media; occasionally since then, new titles' digital or audio releases have preceded the print versions, in reverse of previous practice. Stories in series compilations have also been published individually, as e‑books, and as MP3 or CD "audio shorts".
Series stories have appeared in whole or in part in other Black Library publications, sometimes before the corresponding series books have become generally available; prepublications have included stand-alone releases of compilation stories. "Prerelease" copies of series volumes have been regularly offered months before official publication, in Games Workshop- and Black Library‑sponsored events such as the various Games Days.
There have been a number of special editions and bundles published in a variety of media; bundles have included the "Horus Heresy Collections", which mix editions and media of the same or different titles. Certain special editions are available in limited distribution months before the release of the corresponding regular, or wider-release, versions.
The books' cover art has been separately released, in poster and other formats. Series bundles and special offers have also contained the separate artwork releases of the included titles.

"Premium" editions

English-language series releases include publishing of the titles in special "premium" editions: "Premium Hardback" and "Enhanced Ebook". These versions contain additional material and artwork, and are published several months before their general-availability or regular edition counterparts. The first title to appear in [|"premium" editions], in October 2012, was Angel Exterminatus. The earlier catalogue of the series is also republished in these editions, again beginning October 2012 with the series-opening [|novel trilogy].

Other special editions (selections)

Several novels in The Horus Heresy series have appeared in UK and US science fiction charts, have occupied high positions in Nielsen BookScan genre lists, and since early 2010 have often charted in The New York Times Bestseller List for mass-market paperbacks.
Critical reception of individual titles has been mixed, yet the general tone of reviews has been mostly positive. Although the series overall has been viewed favourably, there have been complaints about its length, the multitude of characters and narrative threads, and the timeline jumps or repetitions caused by the nonlinear storytelling. The evolving series is said to have gradually acquired a backstory and terminology of its own; this has led reviewers to question the accessibility of individual stories to new or casual readers.

Early in its publishing history, the series became a sales success in its category. Horus Rising by Dan Abnett, the opening title, set the pace shortly after its release, topping Locus magazine's "Locus Bestsellers: Gaming-Related" list of August 2006; practically every title in the series had achieved the same or similar performance on this chart. Horus Risings January 2011 [|CD audiobook release] also appeared in ranked sales lists: the edition was number 15 in a related chart published by The Bookseller, covering 2011 UK sales up to September.
Legion by Abnett, and Battle for the Abyss by Ben Counter, were listed in Nielsen BookScan's list of top‑20 fictional works by small publishers for the year ending 23 August 2008; the books appeared in eighth and sixteenth place respectively. The next published title, Mechanicum by Graham McNeill, entered The Booksellers "Top 20 Fiction Heatseekers" chart of 5 December 2008, shortly after its release, at number 10; series titles have consistently appeared in this list.
A Thousand Sons by McNeill was released in February 2010 and arrived at number 22 on The New York Times Bestseller List, the first ever novel on the Black Library imprint to do so. Nemesis by James Swallow followed, reaching number 26 on the List in August 2010. The First Heretic, by Aaron Dembski‑Bowden, reached number 28 in the weekly chart in November 2010 and stayed on the List for a second week, at number 33. Abnett's Prospero Burns was next, reaching number 16 in January 2011; this title also topped a science fiction and fantasy book chart published by The Times in March of the same year.
The compilation Age of Darkness, edited by Christian Dunn, also entered The New York Times Best Sellers List, in May 2011, at number 31. Book 19, Know No Fear, again by Abnett, continued the trend: it appeared at number 21 in March 2012. It was followed on the List by the next series title, The Primarchs, a compilation edited by Dunn, which occupied position 29 during the week of 17 June 2012; in addition, The Primarchs had placed first in Publishers Weekly science fiction bestsellers listing for the week of 28 May 2012. In September 2012 Fear to Tread by Swallow entered The New York Times Best Sellers List at number 13, at the time the highest entry on that chart for a series novel; the book remained on the List the week after, at number 33.

Related works

Between the late–1980s introduction of the Horus Heresy and the start of this series publication in 2006, Games Workshop and affiliates released -branded products that expanded the concept's standing as Warhammer 40,000 background material. The release of such works, which include literature independent of this series, continued as of 2013; the works may relate to it as prequels, sequels, or expansions of its stories.
Pre-series Horus Heresy literature and other related works may have been superseded or rendered obsolete, while other similar material may no longer be authoritative even as it remains in Horus Heresy and Warhammer 40,000 canons; still other non-series Horus Heresy material has been eventually incorporated into the work.
A significant development was the 2012 initial release of the Horus Heresy miniatures wargame expansion, which repositioned the concept as a foreground element within the Warhammer 40,000 gaming system while highlighting the importance of the Horus Heresy to Games Workshop's product lineup and the related universe. The expansion is reputedly developed in coordination with the book series, and includes new material and information about the Horus Heresy and the fictional universe; it joins the series and other works as an authoritative source of Heresy material and Warhammer 40,000 background.
The Black Library and Games Workshop have released novels, game rulebooks, and other products not branded or classified as Horus Heresy, yet directly relating to story arcs or events described in the series. An example is listed in the [|section below].

Selections