Chapter Summaries

After Horus collapsed from a reopened wound at Beta-Garmon, the Sons of Horus struggled to keep his condition secret and feared their faction would fracture without him. As his followers failed to stop his bleeding, Maloghurst resolved to save his master at any cost.

• The surviving rebel forces headed for Ullanor, while Horus remained unconscious aboard the Vengeful Spirit.
• Aximand ordered the execution of witnesses to Horus's collapse to prevent news of his condition from spreading.
• Aximand, Abaddon, Fafnir Rann, and Maloghurst gathered around Horus as the Apothecaries failed to stop his hemorrhage.
• Abaddon admitted he had no solution, and the Sons of Horus lamented that Sejanus was dead and Loken had sided with the Emperor.
• Maloghurst silently vowed to save Horus, no matter the cost.

Maloghurst secretly contacted Erebus and Lorgar to seek a way to save Horus, who was resisting the Chaos Gods. He accepted a cursed ritual dagger and resolved to act before the Legions gathered at Ullanor.

• Maloghurst left the court of the Vengeful Spirit and entered his private ritual chamber.
• He used sacrifices and sorcery to contact Erebus aboard the Fidelitas Lex.
• Erebus and Lorgar told Maloghurst that Horus’s resistance stemmed from a kind fragment of his soul split off by the Dionysian Spear.
• Erebus urged Maloghurst to make Horus submit fully to the Chaos Gods and warned that the Legions would soon gather at Ullanor.
• Maloghurst took the ritual dagger Erebus sent and made his decision.

Maloghurst attempted to save the comatose Horus by using a Word Bearers ritual to enter the Warp and find his soul fragments. He accepted the daemon Amarok’s offer to guide him to Horus, surrendering his soul in exchange.

• Lorgar declared that he would take Horus’s place whether Horus awakened or remained asleep.
• Maloghurst sent the Justaerin away and spent six hours beside Horus, who remained unresponsive.
• Maloghurst performed a sorcerous ritual around Horus and used a ritual dagger to kill himself, sending his soul into the Warp.
• The ritual guided Maloghurst to Amarok, who offered to take him to Horus’s soul in exchange for his soul.
• Maloghurst accepted Amarok’s terms, and the daemon agreed to lead him to Horus.

Maloghurst forced Amarok to guide him through the Warp in search of Horus's soul fragments, then found himself witnessing Horus's triumphant victory at Ullanor. He recognized the vision as false, but it left him facing the memory of his master's greatest moment while the real Horus still bled upon the throne.

• Maloghurst stabbed Amarok with a ritual dagger and threatened to kill it unless it led him to Horus's soul fragments.
• Amarok accepted Maloghurst's oath sworn in the name of The Empyrean and guided him through the Warp.
• Maloghurst followed the scents of dust, gunpowder, and blood until he heard Horus's voice and saw him in ivory-white armor.
• Maloghurst recognized the scene as Ullanor, where Horus and the Luna Wolves celebrated their victory over the Greenskin Orks.
• Maloghurst remembered that the real Horus was still bleeding upon the throne and resolved to expose the false vision.

Maloghurst entered Horus's fractured soul and destroyed the fragment that resisted the Chaos Gods, allowing Horus to awaken aboard the Vengeful Spirit. Horus's wound healed, and he ordered the fleet to Ullanor for the final muster.

• Maloghurst revealed that Horus's triumph at Ullanor was an illusion and showed him the ruined battlefield and the endless war within his soul.
• Horus fought the charging forces while Maloghurst discovered that the wounded fragment of Horus's soul resisted the four Chaos Gods and refused to return.
• Maloghurst sacrificed himself by stabbing Horus's old wound with the ritual dagger, destroying the fragment's resistance and sending its power back to Horus's body.
• Horus awakened aboard the Vengeful Spirit with his wound healed and the Chaos Gods' power flowing through him.
• Horus ordered the fleet to Ullanor, and Abaddon recoiled when Horus's gaze filled him with fear.

After Maloghurst restored Horus by destroying the last goodness in his soul, Horus rallied the rebel forces at Ullanor. Lorgar prepared to challenge him with Fulgrim and Angron, while tensions and suspicions among Lorgar’s sons gave Fulgrim fresh cause for amusement.

• Maloghurst sacrificed himself to restore Horus, who became a slave to Chaos and ordered the rebel fleet to rally at Ullanor.
• Layak announced that Maloghurst had completed the ritual, and Erebus secretly celebrated Horus’s loss of independent will.
• Lorgar declared that Fulgrim and Angron would help him defeat Horus and claim the throne, then summoned Fulgrim with Layak’s aid.
• Fulgrim agreed to help Lorgar and observed the hidden ambitions and resentments among the Word Bearers.
• Lorgar welcomed Argel Tal, while Erebus secretly resolved to kill him and Fulgrim sensed Argel Tal’s doubts about his father.

As the rebel Legions regrouped for the assault on Terra, Mortarion reflected on his distrust of Horus’s growing reliance on Warp sorcery. Calas Typhon confronted him aboard the Endurance, bringing the severed heads of the ship’s Navigators and forcing Mortarion to face what he had done.

• The Ultramarines under Guilliman overwhelmed the Iron Warriors, forcing them to abandon positions and delay the loyalist advance toward Terra.
• The Death Guard traveled aboard the Endurance to Ullanor while Mortarion lamented that Horus had become tainted by Warp power.
• Mortarion resolved to support Horus’s rebellion against the Emperor but no longer regarded Horus as the leader he once admired.
• Calas Typhon entered the council chamber carrying the heads of several mortal Navigators.
• Mortarion recognized the Navigators and demanded to know what Typhon had done.

Mortarion confronted Calas Typhon after Typhon killed the ship’s Navigators, claiming they had betrayed the Death Guard by contacting Malcador. Typhon’s contempt for Mortarion deepened as the primarch struggled to reconcile his principles, his resentment of the Emperor, and the need to obey Horus’s orders.

• Mortarion found that Calas Typhon had killed the ship’s Navigators and demanded a convincing explanation.
• Typhon claimed his men had uncovered evidence that the Navigators secretly communicated with Malcador and betrayed the Death Guard.
• Mortarion refused to inspect Typhon’s psychic memories and ordered him not to use sorcery in his presence.
• Mortarion asked how the legion could travel through the Warp without Navigators and insisted they still had to follow Horus’s orders.
• Typhon recalled Mortarion’s resentment of the Emperor for killing the xenos overlord Mortarion had hoped to defeat himself, and despised him for it.

Typhon recalled how Erebus had guided him to Nurgle and resolved to prove his worth by corrupting Mortarion. After Typhon killed the Navigators and offered to guide the Death Guard through the Warp, Mortarion entrusted him with leading the Legion toward Ullanor.

• Typhon remembered his resentment of Mortarion and his decision to offer the primarch to Nurgle to earn the Kindly Father's favor.
• Typhon reflected on how Erebus had taught him about Nurgle and convinced him that Barbarus's xenos were humanity transformed by the god's power.
• Typhon killed the Navigators, leaving Mortarion with no time to find replacements and forcing him to choose between Horus's orders and Typhon's plan.
• Typhon promised Mortarion that he could navigate the aetheric ocean and guide the Death Guard to Ullanor.
• Mortarion felt an urge to trust Typhon and agreed to let him lead the way.

Calas Typhon led Mortarion and the Death Guard fleet aboard the Terminus Est into the Warp, claiming he was guiding them toward their destination. After Mortarion began suffocating aboard the ship, Typhon revealed that he had become Typhus.

• Calas Typhon persuaded Mortarion to board the Terminus Est, and Mortarion sensed danger while following him to the bridge.
• Mortarion’s numerology warned him that he would face the greatest danger of his life, but he continued to follow Typhon.
• Typhon guided the Death Guard fleet into the Warp, where he laughed and said they would all be reborn.
• The fleet traveled through the Warp for so long that its clocks and sense of direction failed, while Typhon insisted he remained in control.
• Mortarion went to confront Typhon on the empty bridge, began suffocating, and heard the voice declare, “I am Typhus.”

Typhon betrayed Mortarion and the Death Guard, luring them into Nurgle’s garden as Warp plagues overran the Endurance and began corrupting the Legion. Mortarion killed Typhon, but the Death Guard fleet vanished into the Warp, and Mortarion remained trapped in Nurgle’s grasp.

• Mortarion and the Deathshrouds collapsed in agony as Typhon’s voice summoned Nurgle’s power and Mortarion heard the call of a loving father.
• Mortarion realized Typhon had betrayed the Legion, while the Endurance’s Gellar Field failed and Nurgle’s daemons and plagues flooded the ship.
• Warp flies and disease killed mortals and corrupted the Deathshrouds as Nurgle’s garden surrounded the fleet.
• Mortarion charged Typhon and cut him apart with Silence, but Typhon became a swarm of Blight Flies and promised to await Mortarion beside Nurgle.
• The plague overwhelmed the Death Guard, and their fleet disappeared into the Warp as Mortarion’s resistance weakened.

Erebus reflected on Mortarion's corruption as Chaos forces gathered at Ullanor for Horus's assembly and planned assault on Terra. Horus stood ready to receive the arriving Primarchs, but Magnus and Mortarion had not appeared.

• Erebus celebrated Calas Typhon bringing Mortarion to Nurgle and anticipated the gathering at Ullanor.
• Perturabo brought Angron to Ullanor aboard the Iron Blood after subduing him with bombardment.
• The Trisagion arrived with Lorgar, Erebus, Layak, Argel Tal, and Fulgrim, while Chaos forces assembled across Ullanor.
• Perturabo and Angron joined Lorgar and Fulgrim before Horus, who watched from the review stand.
• Magnus and Mortarion remained absent from the gathering without explanation.

At Ullanor, Horus gathered the allied Legions for a review, now transformed by Chaos into a being Abaddon feared he could no longer save. Lorgar prepared to challenge him, secured Fulgrim’s service, and approached the review stand while weighing the uncertain intentions of Omegon, who called himself Alpharius.

• Horus stood above the assembled allied Legions, empowered by the fused forces of the four Chaos gods, while Abaddon feared that Horus’s humanity had vanished.
• Lorgar assessed his allies and believed he had the advantage, though Mortarion and Magnus had not arrived.
• Omegon appeared beneath the review platform, identified himself as Alpharius, and left after Lorgar sensed no hostility toward him.
• Fulgrim accused Lorgar of coveting Horus’s prestige and power, and Lorgar used Fulgrim’s true name to command him as a slave.
• Lorgar promised Fulgrim freedom if he beheaded Horus, then gripped the Illuminator warhammer and walked toward the review stand.

Lorgar launched a coup against Horus at Ullanor, convinced that he could take the Warmaster’s place and rule the forces of Chaos. As both sides prepared for battle, Angron joined the assault, leaving the primarchs on the brink of a fight for supremacy.

• Lorgar approached Horus with his Word Bearers and Fulgrim’s Emperor’s Children, but Horus’s overwhelming presence made Lorgar’s confidence falter.
• Horus ordered the assembled Astartes to rise, while Abaddon and Fafnir Rann prepared the Sons of Horus to retaliate against the hostile Legions.
• Lorgar condemned Horus and raised his Illuminator warhammer, ordering his forces to kill the Warmaster.
• The Word Bearers and Emperor’s Children attacked as Titans and other armies advanced on Horus’s position at Ullanor.
• Angron charged at Horus with his battle-axe, roaring for blood and battle.

Lorgar led Fulgrim and Angron in a ritual-enhanced assault on Horus while their forces tore into the Sons of Horus across Ullanor. As Lorgar appeared to gain the advantage, Perturabo agreed to help the Thousand Sons search for Magnus, claiming he acted out of brotherly affection.

• Lorgar used the Dark Apostle's ritual to bind Fulgrim to the battle and led Fulgrim and Angron in an attack on Horus.
• Lorgar's curses clouded Horus's senses as Fulgrim struck from behind and Angron attacked from the front.
• The Word Bearers and Emperor's Children slaughtered the Sons of Horus while the World Eaters joined the fighting, leaving the rebel legions divided and their victory uncertain.
• Perturabo kept his Iron Warriors behind their fortifications as he questioned the Emperor and heard Ahriman apologize for the Thousand Sons' betrayal.
• Ahriman told Perturabo that Magnus was missing and asked him to help find their primarch, and Perturabo agreed, saying he would do so for the sake of their brotherhood.

Lorgar, Fulgrim, and Angron attacked Horus on Ullanor, but Horus overwhelmed them and left Lorgar near death. Layak refused Lorgar’s order to make Fulgrim fight, and Horus’s victory exposed the rebellion’s fractures.

• The Word Bearers, Emperor’s Children, and World Eaters betrayed the Sons of Horus on Ullanor as other Legions remained neutral.
• Lorgar taunted Horus and attacked alongside Fulgrim and Angron, but Horus calmly blocked their blows.
• Horus struck Lorgar with overwhelming force, shattered his armor, and seized him by the throat.
• Lorgar signaled Layak to force Fulgrim to fight Horus, but Layak refused and called Lorgar a failure.
• Layak’s refusal freed Fulgrim from his true name, while Lorgar lay gravely wounded beneath Horus.

Lorgar’s attempt to overthrow Horus failed after the Wolf Lord fully fused the power of the Four Gods and defeated him. Horus revealed that he planned to defeat the Emperor, then turn against the Chaos Gods, while Lorgar’s allies deserted him.

• Horus overpowered Lorgar and pinned him beneath his foot as the Sons of Horus pushed back the Word Bearers.
• Layak abandoned Lorgar and joined Horus, saying the Empyrean had chosen Horus instead.
• Horus told Lorgar that the Warp Gods had never chosen him and that his betrayal had wasted their strength.
• Lorgar warned that Horus was flawed and destined to lose against the Emperor and the Great Game.
• Horus declared that he would save humanity from the Emperor and then wage war against the Four Gods.
• Fulgrim and Angron went to Horus’s side, leaving Lorgar with only the Word Bearers led by Argel Tal and Erebus.

Horus defeated and humiliated Lorgar, whose Legion had split against him. Angeltai then killed his father with Erebus’s ritual dagger and urged him to ascend to daemonhood, leaving Lorgar beginning the ritual to survive.

• Half the Word Bearers followed Layak and rejected Lorgar, while Angeltai grew more disappointed in his father.
• Horus spared Lorgar, exposed himself to a possible attack, then forced him to kneel and ordered him away.
• Erebus ambushed Angeltai, but Angeltai defeated him and peeled off his face with the ritual dagger.
• Angeltai stabbed Lorgar, held him as he died, and told him he was a failure who could no longer lead the Legion.
• Angeltai urged Lorgar to become a Daemon Prince of Chaos Undivided, and Lorgar began the ascension ritual to survive.

Lorgar was betrayed by Argel Tal and ascended into a Daemon Prince after the Word Bearers sacrificed the dead on Ullanor. He lost control of his Legion as Argel Tal and the surviving Word Bearers pledged themselves to Horus.

• Lorgar realized that Argel Tal had nearly killed him, while the other Word Bearers suppressed those who tried to resist Argel Tal.
• A Chaos ritual on Ullanor sacrificed thousands of dead Astartes and transformed Lorgar into a Daemon Prince.
• Lorgar discovered that his new daemon form could not remain in the material universe without rituals or summoning, and he felt that something precious had vanished from him.
• Fulgrim mocked Lorgar for choosing to cling to life and become a daemon.
• Argel Tal and the surviving Word Bearers knelt before Horus and asked him to lead them.

Perturabo organized the traitor forces on Ullanor while Horus gathered the legions and performed a vast sacrifice before declaring their next destination. The rebel armada set out for Terra to overthrow the Emperor.

• Perturabo used reconnaissance drones to assess events, then accepted Horus's order to direct military forces across Ullanor.
• Perturabo coordinated the warships, supplies, and defenses while brooding over his rivalry with Dorn and his sons' failures.
• The traitor legions and their primarchs gathered on Ullanor, where Horus called for the false Emperor's death.
• Horus's followers sacrificed more than a hundred million mortal slaves, and Layak confirmed that the gods had received the offerings.
• Horus declared that Terra was their next stop, and the rebels boarded their transports and warships.