-->''Bale Rane knew that death would probably hurt. War would probably hurt. Breaking up with your brand new bride and leaving her to go off to war, that would hurt too. Like a bastard.''\\
''He never, ever, in a million light years, expected treachery to hurt so much.''
-->--Creator/DanAbnett, ''Know No Fear''

The Horus Heresy was the greatest tragedy of ''TabletopGame/{{Warhammer 40000}}''. And the writers at Black Library want the readers to feel as much heartache as the characters do.
* The Fall of Horus: The [[IncorruptiblePurePureness pure]] [[WideEyedIdealist idealistic]] and utterly LawfulGood Horus [[FallenHero becoming]] the BigBad.
** Worse: he tried to prevent the future when he and some of his brothers would be condemned and forgotten, and his "father" would be worshipped as god ... only to cause exactly this by his rebellion.
* The kickstarter of the Horus Heresy: the destruction of Monarchia and the humiliation of the Word Bearers Legion. Imagine Lorgar and his Legion, who loved the Emperor so much that he believed he was a god, even writing a book that argued that same point, and went from world to world proselytizing his religion, building grand cathedrals and inspiring masses of people. How did the Emperor respond to their efforts? By having the city of Monarchia (people included), one of the Word Bearer's crowning achievements, burned to ash by their rival Roboute Guilliman and his Ultramarines, and then forcing the entire legion to kneel in the ruins of the city, and then condeming the Word Bearers for their efforts (which had been allowed to occur for the better part of a century)[[note]]Technically speaking, The Ultramarines ordered the people to evacuate the city, gunning down those who resisted. However by the time the Word Bearers arrived to the planet, only seven survivors were found.[[/note]], and say that they all pretty much were failures, with the implication that they better straighten up or they would be purged from existence. Whatever your beliefs or philosophies, it's heartbreaking for a sincere devout son to be slapped down so hard (and perhaps unsurprising that Lorgar's reaction to such would be fury and hate). Seems that a lot of the Horus Heresy could have been avoided if the Emperor treated his Primarchs more like people instead of just soldiers.
** To add another layer of HarsherInHindsight to this, it's subsequently revealed that Guilliman wanted no part in the punishment, as he considered it excessive and needlessly humiliating. Even when Lorgar strikes him in fury, Guilliman's only response is to tell his brother to return to his ship - Roboute actually felt sorry for his brother, but duty compelled him to obey his father's commands, even though it earned him Lorgar's eternal enmity (which would result in many of Guilliman's own worlds suffering the Word Bearers' depredations later in the Heresy).
* The ending to Creator/BenCounter's Literature/HorusHeresy novel ''Galaxy In Flames'', where Saul Tarvitz stands with the surviving members of the Luna Wolves and loyalist Emperor's Children, having bled the traitor armies so badly that even Horus' incredible hubris has been broken, and Horus orders his fleet to bombard the Space Marines into oblivion rather than defeat them on the ground. Even faced with complete and certain annihilation, Tarvitz and his men ''won''.
* The scene where the virus bombs get dropped in ''Flight of the Eisenstein''. Death Guard captain Ullis Temeter and Dreadnought Fal-Huron try to get their own troops to the shelters. Fal tells Temeter to get in as well, since his Dreadnought armor will protect him from the virus. Temeter tells him to eff off as he shoves one last marine into the shelter, then locks the door. As the bombs drop, Temeter realizes that Fal has a couple of cracks in his armor that means the virus will still get him anyway, and the two exchange "you too, huh" one-liners before dying. Made worse by the fact that the defining trait of the Death Guard is their resilience to toxins and disease. Hell, the fate of the entire Death Guard legion could qualify - the traitors got lost in the warp and caught by Nurgle, who made a mockery of their vaunted immune systems. The loyalists become the Inquisition, arguably one of the reasons why life in the Imperium sucks as much as it does.
** Three simple words; "We are betrayed"
*** Rogal Dorn, who has always been seen as the most hardened and stoic among the Primarchs, basically going through disbelief, rage, despair and finally mourning as he faces Horus betrayal; he rages against Garro and Qruze and confronts Keeler, but as the image stream of Oliton's memory is presented to him, he finally realizes and admits the truth. Keeler drives further the power of the scene later, as she sums it up perfectly: The truth has broken up Dorn's hearth, and killed the memory, admiration, loyalty and love he had for his commander and brother, forever.
* In ''Galaxy In Flames'', the last parting of Loken and Tarvitz. Tarvitz says that it may be they will not meet again; Loken says he thinks there's no maybe about it. . . and then, in the scene described above. Tarvitz had desperately gotten to the Emperor's Children so that he could [[DyingAlone die with]] his brothers, in defiance of the breaking of brotherhood that Horus had imposed on them, but at the end, he looks about the survivors -- Emperor's Children, Luna Wolves, World-Eaters -- and realizes that he knows all their names, and that men who had been only faces to him had [[FireForgedFriends become his brothers]].
* On the Warhammer 40K note, the ending of the Horus Heresy novel ''Descent of Angels'' where [[spoiler:Zahariel, the hero of the Dark Angels first battle as a legion (not to mention almost 413 pages of story), is sent back to Caliban with Luther, while his cousin Nemiel stays with the main force because their Primarch distrusts psykers. Anyone who knows their fluff knows what happened at Caliban...]]
** As of "The Primarchs" novella "The Lion", that nightmare scenario has been averted, but in the absolute worst way possible: [[spoiler: During his time in the Crusade, Nemiel became a Brother-Redemptor (predecessor the Dark Angels Interrogator-Chaplains in ''40k'') charged with upholding the Edict of Nikaea banning Librarians. When Lion El'Jonson's flagship gets pulled into a warp-rift allowing Daemons to invade the ''Invincible Reason'', Jonson decides to revoke the Edict of Nikaea after one former-Librarian breaks the Edict and uses his powers to effortlessly destroy one of the Daemons. Nemiel is oath-bound to prevent this, and looks set to fight his own Primarch, when Jonson suddenly lashes out and behead Nemiel with a single swipe. So when Lion El'Jonson finally returns to Caliban, there's little doubt that Zahariel will learn that his cousin was killed by Jonson, and it's doubtful that Zahariel will be feeling much loyalty to his Primarch...]]
* The short story ''After De'shea'', where Angron is so furious over being taken from his band of rebel gladiators he can't properly form a coherent sentence. You know that this guy goes traitor and becomes the leader of the most psychotic group of warriors in an army of psychopaths, but when he's struggling with his loss over his friends, his brothers and sisters, you don't see the Daemon Prince who will burn seventy sectors or doom Armageddon... you see someone who just lost the only family he ever knew. It's really sad.
* Deaths of Kiron and Gythua in ''Outcast Dead''.
* Deaths of Phosis T'kar, Auramagma, Uthizzar and many of the Thousand Sons in A Thousand Sons.
** T'kar's death is one of the hardest. He butchers his way through a horde of Space Wolves and Sisters of Silence, finally reaching the legendary Constantin Valdor who calls him a monster. T'kar sees his reflection in Valdor's armour and realises he has mutated, very extremely. Before he dies he closes his eyes, sheds a tear and responds to Valdor's insult with ''"I know."''
*** When Ahriman is told of this he realises that he did infact consider T'kar a friend, and he is hurt that it took his death to realise that.
** A large part of A Thousand Sons qualify as a tearjerker, considering it deals with the fall of one of the most loyal legions. From what we see, not only did the Thousand Sons comprise of some of the best and most open minded scholars in the whole Imperium, most of them were truly nice and polite and their homeworld a veritable paradise. Too bad, that they became unwitting pawns of Tzentech.
** Magnus's MyGodWhatHaveIDone moment may be one of the most poignant in the entire series. In the previous scene, he executes his plan to warn the Emperor of Horus's treachery, using a powerful spell fuelled by his most potent sorcerers and their thralls to shatter the anti-psyker wards the Emperor had erected in the base of the palace. This was to be his greatest triumph, his proof to his father that Nikea was wrong and that psychic powers could be used for good. It all goes wrong in the most terrible way possible - as Magnus manifests as a horrible monster beneath Terra, he and the Emperor's minds touch upon one another and Magnus realizes that he has just completely scuppered the Emperor's plans. His intrusion had destroyed the delicate wards holding the Warp back and sundered any chance for the Emperor to complete his greatest work; his treachery had closed off a future where he was to use the awesome might of the Golden Throne to help humanity rule the stars; worst of all, he knew he and his legion were going to be hunted down and destroyed by the Space Wolves for their defiance of the Emperor's will. Upon returning to his corporeal body, he flees to his chambers and destroys them in a guilt-wracked rage, before beginning to lay out the plans to [[RedemptionEqualsDeath render Prospero defenceless]].
* Most of the scenes involving Argel Tal in ''The First Heretic'', particularly straight before he orders that the Word Bearers fire upon the loyalists on Istvaan.
** The epilogue deserves a special mention: [[spoiler: Argel Tal is sitting in his quarters looking at the data slate that Cyrene was writing when she was killed. Following this, he looks at Aquillon's sword, the very weapon which killed Cyrene. Argel Tal and the Gal Vorbak then killed Aquillon and his fellow Custodes, but not before Xaphen and several other Gal Vorbak are killed. Looking at these memories of the three closest people in his life, Argel Tal reflects that all his brothers are dead. And then comes the absolute bitterest knife twist in the book:]]
-->[[spoiler: '''[[DemonicPossession Raum:]]''' [[FalseReassurance No. I am your brother]].]]
* Solomon Demeter in ''Fulgrim''. He is defending the Precentor's Palace and finds his fellow Istvaan loyalist Lucius fighting a squad of Emperor's Children marines. Solomon rushes in to kill them, which the two of them do easily. Only once they are dead does he realise that they too were Istvaan loyalists! Lucius is the real traitor. Before he can do anything Lucius fatally wounds him and declares Solomon, Tarvitz and all the other loyalists to be fools, and that he will not die with them. Solomon sheds a single tear as he dies and sees the skies begin to rain.
* In ''Know No Fear'', Venatus realises that the Mechanicus server has blood on her sleeves, realising that someone died, cradled in her arms.
** Later, Tawren reveals the identity of the man who died in her arms with the following words:
---> He was, I suppose, my husband. My life partner. The Mechanicum does not think in such old-fashioned terms, and our social connections are more subtle. But yes, captain, we were close. A binary form. I miss him. I do this for him.
** Also, Magos Uldort. She volunteered to remain at a command center that was about to be overrun by the enemy, fully aware that it was a death sentence. She nonetheless performed her duties diligently and directed all possible reinforcements to help Tawren and Venantus. Because of her, Tawren was able to retake control of the Calth defense grid, which in turn saved the remaining Ultramarines and their Primarch. The reader never sees her final moments, nor will they ever see her speak a single line. But the bittersweet triumph at Calth will ultimately be owed to her.
* Serena D'Angelus's story in '''Fulgrim''' is one long BreakTheCutie TearJerker with sides of NightmareFuel. A kind and gentle painter who is friends with Ostian Delafour she is one of the Remembrancers sent down to the Laer homeworld after the conquest, though she only goes after Ostian convinces her to even though he can't because he spurned another Remembrancer's unwanted advances and was actually quite prepared to not go because her friend can't, and is [[spoiler: infected by the Laer Temple's Slaaneshi taint. The corruption preys on her already existing low self-esteem and convinces her that her work, which is actually extremely good, is sub-par and that she is a fraud. She slowly begins going mad, and when Ostian attempts to help her she insults him for his pity which results in him severing ties with her, though as he leaves she begs him not to. After this she seduces another Remembrancer and brings him to her room, sleeps with him and murders him at the climax, using his blood and other bodily fluids for paint. After a long period of blankness, where it is implied she did this a lot more, the corruption fades and she seeks out the one person she thinks might be able to help her, only to find that Ostian has already been murdered whereupon she realizes that he was only trying to help her. With nothing left, Serena declares that she loved Ostian but was too afraid to tell him, and kills herself by driving herself onto the same marble blade that Ostian is impaled on.]] A truly tragic story that shows just how insidious the taint of Slaanesh really is.
* Hell, the entire plotline of Prospero Burns and A Thousand Sons. Two brothers, almost polar opposites, but on the same side; one tries desperately to warn their father of an impending disaster, the other begs, even as he is on the way to kill his sibling, for the other to stand down and set aside what he sees as foolish heresy. Both brothers genuinely just want the best for the other. But Daemons, distrust and plain old terrible luck conspire to see the destruction of the two most deadly threats to Horus. Just to emphasise: Leman Russ and Magnus The Red disliked, distrusted and '''loved''' each other.
* Fulgrim's MyGodWhatHaveIDone moment in ''Fulgrim''. Right after [[spoiler:killing Ferrus Mannus,]] his most beloved brother Primarch, Fulgrim realizes that everything that he took as a slight towards him from Ferrus were actually well-meant jests, and that he had doomed his Legion to heresy the moment he had taken the blade from the Laer temple.
** Moments like that run throughout the Horus Heresy, and it makes the whole thing much sadder when you realize that a lot of the pain and bloodshed of the heresy was ''completely unnecessary.''
** And then the absolute tragedy of the event: [[spoiler: Standing over Ferrus Manus' body, Fulgrim realizes what he and the Emperor's Children have become, and begs the Daemon in his sword to end his pain. The Daemon proceeds to possess Fulgrim, forcing his mind into a painting of Fulgrim on the ''Pride of the Emperor''. For the better part of five years the fandom assumes that the Daemon was responsible for Fulgrim's subsequent atrocities, until ''The Primarchs'' novella ''The Reflection Crack'd'', where it's learned that Fulgrim was able to forcibly swap places with the Daemon, but the effort drove him completely into the embrace of Slaanesh, and now doesn't regret killing Ferrus Manus. What ''40K'' has been telling us for years was proven true in the tragedy of Fulgrim: No one who has touched Chaos can ever escape it.]]
* This bit of MentalWorld [[TheReveal dialogue]] between [[JerkassWoobie Kai Zulane]] and [[spoiler:the Emperor]] in ''The Outcast Dead'':
---> 'But you're going to die.'
---> 'I know,' said [[spoiler: the Emperor]].
* The confrontation between Sanguinius and Alotros in the beginning of ''Fear To Tread''. Alotros has succumbed to the Red Thirst, which unlike the Black Rage predates the Horus Heresy and has slowly begun to emerge among the Blood Angels Legion. Alotros is drinking the blood of fallen Nephilim, and Sanguinius tries to reason with him, hoping against hope that he can bring his gene-son from the depths of insanity. Alotros stares at his Primarch for moment, then attacks him, forcing Sanguinius to kill him in self-defense just as much as it was giving Alotros [[MercyKill the Emperor's Peace]]. For years fans have speculated that Sanguinius's presence might be able to bring Blood Angels back from the depths of the Flaw. As of ''Fear To Tread'', that theory is {{Jossed}} with extreme prejudice.
** Really, the entire prologue, showing Horus and Sanguinius talking as loving brothers, with Sanguinius even trusting Horus enough to tell him about the flaw in the Blood Angels legion, and confiding that he's afraid his legion is going to be wiped from Imperial history. It really shows that these two brothers genuinely loved each other. Those who know their 40k backstory know that [[spoiler: Horus kills Sanguinius, and he doesn't make it quick or painless.]]
** The fate of [[spoiler:Meros]] is also pretty damn depressing even by 40K standards. [[spoiler:Most {{Heroic Sacrifice}}s are at least merciful enough to kill you. Meros's, however...death would probably be preferable.]]
* Courtesy Perturabo in ''Angel Exterminatus'':
-->''[[HiddenDepths You don't know my dreams, brother.]] Nobody ever cared enough to find out.''
** His actual dreams are equally sad. His ideal world is one where he's designed beautiful, functional cities that are the centre of culture, learning, and every other civilised virtue. He's not even fussed about being the ruler of it. And he knows that it will never ever come to pass.
* When Guilliman finally catches up with Lorgar in Betrayer. The look of total, all consuming hatred on Roboute's face makes Lorgar realize that Guilliman never despised him the way Lorgar had always assumed he had. It's not quite a MyGodWhatHaveIDone moment, but it speaks volumes that Lorgar feels ashamed that so many of his actions have been led by an entirely false opinion of his brother, and feels a need to try and justify his actions.
** While a character's death almost always gives the reader some sorrow, [[spoiler:Argel Tal's]] was particularly heartbreaking. Having one of the most compassionate, and arguably most human, characters in the series die such a way hit pretty hard; the fact that everyone thought he was going to have a more dignified death (since his death was a ForegoneConclusion) did not help.
* The state Vulkan is in after ''Vulkan Lives''. [[spoiler: Captured by Konrad Curze, it was discovered during his torture that Vulkan was a Perpetual, a being who cannot die. Enraged that he couldn't kill him, Curze repeatedly killed Vulkan, destroying his mind. By the time he managed to find his hammer ''Dawnbringer'', which had a built in teleporter, he was devolving into a raving maniac. The teleport function allowed him to escape the ''Nightfall'', but he teleported into Macragge's atmosphere and burned up on reentry, and survived again. Unfortunately, when discovered by the Ultramarines in ''The Unremembered Empire'', the constant deaths had driven Vulkan completely insane (even by 40k's broad definition of the word) trying to attack everyone he saw. The Cabal, the group responsible for the Alpha Legion's defection to Horus, wanted Vulkan killed to prevent him from returning to Terra and helping the Emperor, but Eldrad Ulthran told John Grammaticus that by using a fulgurite spear imbued with the Emperor's psychic lighting could heal Vulkan's mind instead of kill him. Grammaticus stabbed Vulkan, but it failed and Vulkan died. We get a brief HopeSpot where Guilliman and a group of Salamanders maintain that Vulkan merely needs time to heal (one Salamander thinks he heard a heartbeat) until we learn the name of the preservation capsule containing Vulkan's body: The ''Unbound Flame'', the last and most mysterious of the Artefacts of Vulkan that the Salamanders believe their Primarch left for them to find when he departed.]]
* The Wolf of Ash and Fire
--> I was there, he would say, right up until the day he died, after which he spoke only infrequently. I was there the day Horus saved the Emperor.
** This entire story is a TearJerker. The Emperor and Horus had such a good relationship with each other, and at the end of the story [[spoiler: they set course for the place where it all begins to go wrong. Ullanor.]] It's heartbreakingly sad seeing these two so close, knowing that soon they'll be enemies and that the Horus we're seeing now is soon going to be gone and replaced by the evil Warmaster Horus.
** It's also a TearJerker because we get to see all the familiar faces of the Luna Wolves, before the NightmareFuel that was Istvaan III. Tarik Torgaddon and Hastur Sejanus joking with each other over strategy, Horus Aximand being the voice of reason, and Abaddon striving to make his Primarch proud. They'll never be like that again...
* Legion of One
--> ''I have no brothers. Only traitors remain. I am a Legion of one and I will kill you all until death comes to take me!''
** The scene where Cerberus (who fans of the series will already have recognized as [[spoiler: Gavriel Loken]]) returns to the place where he was nearly slain and speak to his brother... who is long dead. He is a broken, tormented thing, trapped in a literal hell, unable to die and unable to remember what happened to him. Every time he tries to remember, he suffers beyond imagination, and yet he tries, again and again, desperate to understand what happened - and to remember the name of his dead brother...
* Pharos
** The Night Lords brothers Kellendvar and Kellenkir [[spoiler: each meeting a sad fate. Kellenkir becomes tainted through contact with a Daemon Weapon and ends up being mercy killed by the little brother he once protected when they were children, and goes out wishing he'd killed him years ago. While Kellendvar is forced to execute his brother after realizing he is beyond help, and accepting that his Primarch was right that there is no such thing as hope, the act leaves him so broken he simply stands up and lets the Ultramarines kill him without any resistance.]]
** When Sanguinius is confronted by [[spoiler: Konrad Curze, the Angel sees firsthand how broken the Night Haunter is through his hellish childhood on a world filled with the worst of humanity, a world that he tried to save and as soon as he was gone slid right back into depravity, through the agonizing visions that constantly bombard him with exactly how he is going to die and how miserable the galaxy is going to become, and through the simple fact that Curze always believed his brothers hated him because he was eerie and hard to be around, a fact that Sanguinius knows isn't true and tries to tell him, but Curze is too far gone to listen. The entire scene basically shows that underneath the torture, apathy and terrifying visage; Konrad Curze is somebody who tried so damn hard to be a better person, but could never quite reach that goal.]]
** Dantioch's [[spoiler: HeroicSacrifice to banish Krukesh the Pale and the Night Lords from the Pharos, his motivation being the desire to protect his friend Alexis Polux, results in his death. When the Ultramarines arrive they find Polux, an Imperial Fist, weeping over his friend's body and refusing to let anyone touch him. Even when the funeral bier arrives Polux carries it solo.]]
*** The Warsmith's [[spoiler: funeral is also a TearJerker, but doubles as a Heartwarming moment, as Guilliman himself declares Dantioch a Hero of the Imperium, and the Ultramarines give him a 21-bolter salute.]]
*** Also, consider Polux's point of view on the entire situation. [[spoiler:Dantioch is now the ''second'' BigBrotherMentor whom Alexis considers better than himself and whom he loses to a HeroicSacrifice]].
** While Guilliman's speech at the end [[spoiler: that Sotha will never again fall to an enemy]] is a moment of Awesome, those with foreknowledge of 40k will also consider it a sad moment, [[spoiler: as Sotha's death is already set in stone at the jaws of the Tyranids, the race ironically summoned to the Milky Way by the actions of the Legions at Sotha.]] Even as Guilliman gave his speech, [[spoiler: Sotha was already doomed.]]
*** There is another scene in Guilliman's speech that is a bitter pill to swallow. While praising the actions of the 199th "Aegida" Company, he awards them a new company badge: [[spoiler:Twin scythes. The 199th Company are the Ultramarines who will form the Scythes of the Emperor, the Space Marine chapter which lived on Sotha, and is dying out now that the Tyranids have destroyed their homeworld and most of its battle-brothers.]]
** While learning to use the Pharos to illuminate far off worlds, Polux involuntarily turns the Pharos to see his primarch, Rogal Dorn. Polux begins desperately crying out "My Lord! My Lord! Hear your son!" before the vision vanishes. The last thing he shouts before Dorn disappears from his sight? [[spoiler: ''"Father!"'']] The text notes that he is near to outright tears.

* Angels of Caliban
** [[spoiler: Sanguinius finds out through Cruze and the Lion that he is going to die and what does he do he just accepts it and says "To die at Horus's hand is a fate I gladly accept, if it means that the Emperor yet lives and fights for mankind, I would speed to this confrontation on the swiftest of wings if it means the enduring reign of the Emperor." This guy now knew he would die but was ready to do so regardless of it, also a chapter or more before that the Lion after getting kicked out of Imperium Secundus, he wonders if he had not been blinded by his hunt for Cruze would he have been able to save Sanguinius. Despite being banished by said brother he still wanted save him and blames himself for not being able to.]]

* ''The Path of Heaven'' features [[spoiler:the heroic sacrifice of Stormseer Targutai Yesgeui. With the White Scars trapped by the Death Guard and the Emperor's Children, Yesgeui places himself inside a device that, like the Golden Throne, was part of the Emperor's plan to gain control of the Webway and thus remove the need for the Warp. Even knowing he will die, Yesgeui activates the device to allow his Legion and his primarch to escape their enemies and get back to Terra. His last act before the machine consumes him is to telepathically say goodbye to his three closest companions; Revuel Arvida, Ilya Ravallion and Jaghatai Khan. His last words to them are particularly heartrending]]:
** [[spoiler: To Arvida, Yesgeui asks him to hold back the flesh-change threatening to consume him long enough to get the White Scars safely back to Terra, as he is the only one who can]].
** [[spoiler: Yesgeui tells Ilya that she was TheHeart of the legion, and says she shouldn't mourn him for doing what a Space Marine should]].
-->'''Yesgeui''': [[spoiler: Do not grieve. We were made to do this, ''[[AffectionateNickname szu]]''. We were made to die]].
** Not that Ilya's response doesn't cut hard as well:
-->'''Ilya''':[[spoiler: Not you! Anyone but you!]]
** [[spoiler: To the Khan, Yesgeui asks his Primarch not to let the Legion slip into despair and hatred like their enemies, and to keep them safe and together in the battles to come, all while Jaghatai is desperately begging his old friend and mentor not to do it]].
-->'''[[spoiler: Jaghatai Khan]]''': [[spoiler: Targutai, this will end you. Do ''not'' do it. Return to the ship]].
-->'''[[spoiler: Yesgeui]]''': [[spoiler: Know that [[ItHasBeenAnHonor I would have followed you to the end. I would have stood beside you on Terra]]. When I am gone, do not let them forget. Do not let them become that which is hateful.]]
-->'''[[spoiler: Jaghatai Khan]]''': [[spoiler: Come back...[[PleaseDontLeaveMe I still need you]].]]
** It gets even heavier as Jaghatai tries to process what is happening. [[spoiler: the last of the friends he had on Chogoris is gone, and he is left alone, watching his Legion die.]]
* ''The Master of Mankind'' features one of the saddest moments in all of the Heresy. Forced to enact the "Unspoken Sanction" in response to the Daemonic incursion in the Webway, [[spoiler: it is revealed that this is the moment when the Imperium begins sacrificing psykers to the Golden Throne to keep it active. Gathering a thousand psykers to be sacrificed, a duty that even the Sisters of Silence don't enjoy, these poor souls are hooked up to the Golden Throne and used to fuel it so that the Emperor can leave it's confines, for a single day. And the reader sees this through the eyes of a teenage girl whose low-level psyker ability allows her to hear the dead, and who is the first to burn up and die.]]
** The heartbreaking final scene in the book [[spoiler: when the Emperor admits to Diocletion that no matter how the Heresy goes now, Chaos has won and humanity is doomed to a slow agonizing extinction. The dream he had was beautiful and he knows now that because of one idiot's ignorance and another's childish petulance, humanity will never escape the grip of Chaos. It becomes even worse when he admits at the very end that he doesn't know what to do next, this almost-god who has always known what he needs to do next and what must be done is blind.]]

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