Emperor Of Mankind's History
The Emperor of Mankind, often referred to by His faithful as the "God-Emperor," the "Master of Mankind," or simply "the Emperor," is the immortal Perpetual and psyker who serves as the reigning monarch of the Imperium of Man, and is described by the Imperial Ecclesiarchy and the Imperial Cult as the Father, Guardian and God of Humanity.
The Chaos Gods and the Daemons of the Warp refer to Him as "the Anathema" for He is the greatest embodiment of universal order in the galaxy today and the most potent foe of Chaos in existence. He was, and remains, the most powerful Human psyker to have ever been born.
He has sat immobile, His body slowly crumbling, within the Golden Throne of Terra for over 10,000 standard years. Although once a living man, His shattered, decaying body can no longer support life, and it is kept intact only by the cybernetic mechanisms of the Golden Throne and a potent mind itself sustained by the daily sacrifice of thousands of lives.
The Emperor chose to sacrifice His immortal life at the end of the Horus Heresy in the service and protection of Mankind. To Humanity's countless trillions across the galaxy-spanning Imperium, He is nothing less than God. Through His Imperium, Humanity is united and remains one of the most powerful intelligent species in the Milky Way Galaxy as well as its most dominant in terms of both population and territory held.
United under one government, Mankind is able to survive the myriad deadly threats it faces from aliens, the forces of Chaos and the Traitors, Heretics and mutants that lie within the Imperium's boundaries.
The Imperium's rule, carried on in the Emperor's name since the end of the Horus Heresy by the High Lords of Terra and a multitude of Imperial organisations, has been long, oppressive and necessarily harsh.
It has also resulted in technological and cultural stagnation, and a regression into tyranny, superstition and religious obfuscation and intolerance that would have horrified the Emperor.
Though He is no longer responsive to external stimuli, the Emperor still lies at the very heart of the Imperium's continued existence. Although He cannot be directly involved in the day-to-day running of Humanity's galactic government, His existence on the Golden Throne is vital to sustaining the Imperium, since His powerful mind's presence in the Immaterium maintains and directs the Astronomican, the psychic beacon that makes possible faster-than-light Warp travel and is vital to Imperial shipping, transportation, commerce and communication.
However, the maintenance of this beacon requires the aid of other psykers, whose lifeforces are slowly drained away by the Emperor to power the beacon. One thousand psykers a day give their lives to maintain the Emperor's psychic strength.
He is said to still guide His race through the psychically-reactive divination tool known as the Emperor's Tarot, which select psykers can consult to gain a glimpse of the future and the Emperor's will. He is also said to constantly battle the Chaos Gods in the Warp and prevent their further intrusion upon the material universe.
His mind must remain vigilant at all times throughout the entire Imperium to safeguard the Human race and to offer His protection to the faithful. Above all else, it is Mankind's collective belief in the Emperor's divinity that serves as its greatest protection from Chaos and the other hideous dangers that plague the galaxy. As the Imperial Creed has taught for over 10,000 standard years, the Emperor protects...
History
Original Origin
The Emperor is the collective reincarnation of all the shamans of Neolithic Humanity's various peoples, the first Human psykers. The foul Warp entities that would become the four Great Powers of Chaos had not yet fully formed when the Emperor was born on Earth during prehistoric times, somewhere in ancient central Anatolia (modern Turkey) in the 8th Millennium B.C.
But even before the birth of the Emperor, as Humanity grew and progressed, the Warp began to become increasingly disturbed by the dark undercurrents of Humanity's collective psyche, and the shamans began to lose their former ability to reincarnate into new bodies. Instead, upon dying, their souls were consumed by the entities and Daemons of the Warp.
Eventually the shamans of Humanity, unable to reincarnate, would become extinct, and without the shamans and their psychic abilities to guide the race, Humanity would inevitably fall prey to the corruptions of Chaos, just as eventually happened to the Aeldari. In these ancient days, all the shamans of Earth gathered in a grand conclave to decide what must be done to stave off the day when they had all been consumed by the Warp.
In the end, the shamans decided to pool their collective psychic energies by reincarnating as a single soul in a single Human body to create an individual they called "the New Man." The thousands of shamans, as one, took poison, and as one, they died, their souls flowing into the Immaterium in a rush of psychic power that overwhelmed those Daemons who sought to feast upon it with a cleansing, purifying fire, a flame imperishable that became one soul out of many.
A standard year later the child who would become the Emperor was born in a Neolithic settlement of Anatolian herders and farmers of a normal mother and father, with normal brothers and sisters. His psychic power was so great that its energies altered His genome and physiology in the womb and rendered Him immortal so He would no longer need to reincarnate and could not be assaulted by the daemonic creatures of the Immaterium upon His death. As He grew older, His potent psychic powers began to manifest.
For thirty-eight thousand Terran years, He wandered over the Earth and throughout Human history. He travelled among the different peoples of Mankind. While He had first been only an observer of Mankind's triumphs and follies, He soon began to help where He could, using His ancient wisdom to spread efficient government, crop management, animal husbandry, technology and peace. He used His influence carefully, at first adopting only the guise of a normal man, and without revealing His true nature.
As the millennia passed, the man who would become the Emperor watched the Human race develop. He travelled the entire globe, watching and helping, sometimes adopting the persona of a great leader or advisor. In times of trouble He became a crusader, a religious leader or even a messiah, at other times He remained a back-stage contributor to events, an advisor to kings, a court magician, a pioneering scientist.
Many of the guises He adopted were humble, others became monumental figures of world history or religion. At times of crisis He would be there, steering the Human race along a narrow path to survival that only He could see.
As the Human race prospered and advanced the Warp became increasingly disturbed. The man who would become the Emperor was aware of how the extreme sides of the Human character were feeding the nascent Chaos Powers. Despite His best efforts to promote peace and harmony across Old Earth, the instinctive values of martial honour, ambition, defiance, and self-satisfaction could never be eradicated from the Human character.
Some of the New Man's plans proved less than successful; seeds of wisdom often failed to flourish or grew into uncontrollable monstrosities leading to eras of persecution and war.
The Chaos Gods sensed the presence of the New Man, the "Anathema" as they would name Him, and His efforts to curb their own power and growth. Even before they became fully conscious in the Immaterium the Ruinous Powers recognised the man who would become the Emperor as their greatest enemy.
Khorne was the first of the four major Chaos Gods to wake fully, and an era of wars and conflict soon raged across the globe to herald his birth. Tzeentch was the next, and nations and politics soon grew to maturity with all of their implicit intrigues and double-dealings.
Nurgle was the third to awake and plagues swept across Old Earth's continents claiming many souls for the Lord of Decay. By the end of the European Middle Ages on Terra, all three of these Chaos Gods had awoken to full consciousness. The fourth, Slaanesh, still slumbered, to be awakened by the follies of a different species, the Aeldari.
But as the New Man's psychic powers further developed, He became ever more aware of the terrible dangers that awaited Mankind in the broader universe and He resolved to do all in His power to defend and guide Humanity towards a future as the predominant species in the galaxy.
As more and more Humans were born with the mutant psyker genes that granted them the ability to wield the potent power of the Immaterium in the last centuries of the Dark Age of Technology, and Humanity suffered from the deadly effects of uncontrolled psykers that heralded the onset of the Age of Strife, the Emperor realised that He would have to take a more direct and open role in Human affairs than ever before.
Following the birth of Slaanesh after the Fall of the Aeldari in the 30th Millennium, and the end of the Warp Storms that had prevented interstellar communications and travel from the Sol System, the Emperor determined that the time had come to directly steer the history of Humanity once more, or see the Human race ultimately go extinct due to the troubles of Old Night.
Current Origin
However, the above account is now considered largely apocryphal. In truth, the Emperor's origin and history prior to unifying Terra is largely mysterious and undetailed, though His immortality and extraordinary psychic abilities still define Him.
The first mention of the Emperor by that name in Imperial records is when He unified Terra at the end of the Age of Strife in the 30th Millennium. Horus mentions that the Emperor lived "in Anatolia, in his own childhood" when talking of his first meeting with the Emperor. It is known that He had been immortal and ancient even before His ascension to the Golden Throne over 10,000 Terran years ago.
The Emperor is the "New Man," the first and greatest of the new race of Human psykers. He is also the collective reincarnation of the extinct shamans, sorcerers and wise-men who had guided primitive Humanity during prehistoric times.
As the Emperor grew older His powers began to manifest themselves and become more potent and He gradually remembered His thousands of past lives, adding all of their knowledge and experience to His own.
One account of the Emperor's origin goes so far as to say that He had mortal brothers and sisters and claims that He was born in the 8th Millennium B.C. in a primitive Neolithic village along the banks of the Sakarya River in Anatolia.
While he was still an adolescent, the Emperor's father was murdered by his uncle. While preparing his father's body for a primitive funeral ritual, he received a clairvoyant vision of his murder. Later, the boy who would become the Emperor calmly approached His uncle and stopped his heart with a slight use of His telekinetic psychic abilities, displaying neither sorrow nor malice for the deed.
According to the Emperor Himself, this was the moment He realised that Humanity needed law, order, and the guidance of a ruler to reach its full potential. At some time after, He left His village for the "first city of Humanity," likely one of the Sumerian city-states of ancient Mesopotamia.
For thousands of standard years before becoming the Emperor, He guided and watched Humanity develop over the course of its history, assuming the guise of a large number of historical personages. He was aware that the darker extremes of Human nature were feeding the growth of the Chaos Gods in the Warp, and so He sought to promote peace and harmony on Earth and thereby curb the growth of the Ruinous Powers' strength.
Whatever His true origins, the man who would become the Emperor was the most powerful psyker ever born among Humans. Before the Emperor began His rise to power, He was also an anonymous Perpetual, a member of a mutant branch of Mankind gifted with effective immortality due to extremely rapid and efficient cellular regeneration.
Whether this ability of the Perpetuals came about naturally or was artificially induced is unknown, but the Emperor was present during the time of Humanity's prior star-spanning civilisation in the period now named the Dark Age of Technology. He was known to associate with other Perpetuals like Himself in that era. Among these was a woman named Alivia Sureka.
Together, she, several other Perpetuals and the man who would one day become the Emperor travelled to the Knight World of Molech aboard a one-way voidcraft. There, they discovered a Warp Gate into the Realm of Chaos which the future Emperor entered.
He forged an unknown bargain with the Chaos Gods and was imbued with new powers and the knowledge required to ultimately create the primarchs. The Emperor left Sureka behind to look after the Molech Gate until such time as the world could be safely protected by the coming of the future Imperium of Man.
Despite His early dealings with them, the Chaos Gods themselves later recognised the Emperor as their greatest enemy among all the intelligent beings of the galaxy, naming him "the Anathema." Only at the end of the Age of Strife did the Emperor emerge from obscurity to take a more direct hand in the future of Humanity, conquering the warring factions of Mankind's homeworld and establishing His direct rule over Old Earth.
The Emperor accepted the deaths of the many innocents that resulted from His conquest with great remorse in order to achieve the greater good of unifying Humanity and protecting it from the manifest predations of the Warp.
With the assistance of the ancient Mechanicum on Mars, who joined with the Emperor and the people of Terra in the Treaty of Mars that formally founded the Imperium of Man in the late 30th Millennium, the Emperor created the first Space Marines and fleets of interstellar starships that would carry His armies across galactic space.
The objective was a Great Crusade that would unify all of the planets colonised by Humanity during the Dark Age of Technology prior to the Age of Strife into one Imperium of Man. The crusade would also subdue, destroy, or force into exile all intelligent alien races from the Milky Way Galaxy. The galaxy was to become the Imperial Domain, the manifest destiny of Humanity.
The Emperor also created the superhuman primarchs from whom the Space Marines' gene-seed was later developed to serve as His primary military commanders for the Great Crusade. The Chaos Gods, however, sought to thwart the Emperor's grand plan. The primarchs were sucked into the Warp even as they gestated in the gene-laboratories deep beneath the Imperial Palace, and were scattered across the inhabited worlds of the galaxy.
During the Great Crusade all but two of the twenty primarchs were found and united with the Space Marine Legions that had been created after their disappearances from the genetic material that they had left behind. As the Emperor traveled across the stars, some Humans wanted to worship Him as a god, however He forbade this, proclaiming, "I am not a god; rather than enslaving Humanity I want to free it from ignorance and superstition."
However, Lorgar, the primarch of the Word Bearers Legion, desperate to find some outlet for his belief that Humanity must have a god to worship to be truly whole, gave in to the constant whispers of the Chaos Gods and, after corrupting his Legion to their service, sent his First Chaplain Erebus to poison the minds of the other primarchs and their Legions.
Just as the Imperium had reached its apex in the first decade of the 31st Millennium, the Emperor's most trusted son, the Primarch Horus of the Luna Wolves Legion (later renamed the Sons of Horus), fell to Chaos as a result of his own pride, need and ambition. Horus betrayed the Emperor, and along with fully half the Space Marine Legions and Imperial Army regiments, initiated a massive civil war for control of the galaxy.
This rebellion is known to history as the Horus Heresy. Though the Emperor ultimately defeated Horus during the Traitor Legions' assault on Terra, He was all but slain in the battle after suffering a crippling loss of limbs and mortal systemic damage; only the life-supporting Golden Throne has sustained His living corpse in a kind of stasis, neither dead nor truly alive.
Trapped within His prison of flesh, only the Emperor's mind is allowed to wander free within the Immaterium, still seeking to protect and guide Humanity to an increasingly distant better future.
Unification Wars
The man who would later become known as the Emperor of Mankind first appears in Imperial records as just one of the many warlords struggling for control of Terra during the later part of the Age of Strife in the 30th Millennium.
The Emperor undertook a series of military campaigns against all the other techno-barbarian warlords on the planet that would collectively later become known as the Unification Wars.
During these conflicts the Emperor employed several military formations -- such as the warriors of the unit designated Geno 5-2 Chiliad who would go on to serve in the Imperial Army -- that consisted of genetically-enhanced warriors to maximise His tactical prowess. The most powerful of these troops were the proto-Astartes known as the Thunder Warriors.
Though physically the most potent of His creations, more deadly in combat than even the later Space Marines, the Thunder Warriors were far from perfect. Having been created from adult troops who had undergone a rapid process of genetic, bionic and chemical augmentation, many did have difficulty coping with the physiological changes.
Metabolic collapse leading to rapid death was not uncommon, and many Thunder Warriors were also prone to mental instability and even psychosis as they aged.
These warriors played a significant role in the Emperor's eventual victory over all the other warlords of Terra and led Him to believe that His future plans to reunite Mankind would require the creation of an even more potent core of genetically-engineered military commanders and warriors.
Following the Battle of Mount Ararat in the Kingdom of Urartu, which was the last battle of the Unification Wars, the Unity of Old Earth was at last achieved after decades of blood, loss and fire. With this victory, the planet and population of Terra were at last unified under the single rule of the Emperor.
But to make His dream of reuniting all of Humanity within a single galaxy-spanning empire possible, the Emperor knew that He would have to make some difficult, even immoral decisions.
Their purpose having been achieved, the Emperor ordered all of the remaining Thunder Warriors to be liquidated. Their imperfections and propensity for mental decay rendered them a dangerous group of warriors to leave alive in a time of peace. They needed to be removed to make way for their eventual successors, the Primarchs and the Space Marines.
In truth, the Emperor was right to be worried about His creations. Another source claims that even before the Unification Wars had ended, the Thunder Warriors at last realised that their creator had cursed them with short lifespans as a result of their imperfect genetic augmentations, and turned upon Him for what they saw as His betrayal.
It was a cadre of several hundred Custodians, even then believed to have been commanded by the legendary Constantin Valdor, and accompanied by several thousand prototype Astartes of the I Legion of the newborn Space Marines, that stood in the Emperor's defence, carrying out a merciless culling of the obsolete and rebellious gene-soldiers.
Though some Thunder Warriors successfully escaped the cull, however it happened, the vast majority of those who survived the Unification Wars died at the hands of their own allies.
Individually or in small groups -- like the self-stylised "Dait'Tar" Thunder Warriors present during the Cerberus Insurrection of the early Great Crusade era -- some Thunder Warriors would survive, living mostly anonymous and miserable lives amongst the population of Terra, all honours of the past forsaken, always fearful of being discovered.
Fortunately for these survivors, the Imperium, believing them all dead, never truly sought to hunt them down, as all efforts were by now concentrated on the progress of the Great Crusade.
Official Imperial propaganda proclaimed that the Thunder Warriors had heroically died to the last man during the Battle of Mount Ararat, the greatest of their number, Arik Taranis, surviving just long enough to raise the Emperor's banner when victory, and unity, was achieved.
But the Emperor could not wipe away the stain entirely, for several Thunder Warriors managed to escape what they called "the Culling," including Arik Taranis, who would yet have a role to play in the fate of the Emperor's realm.
With the Unification of Terra achieved, the Emperor next set in motion His plan to defend and better Humanity across the galaxy, by unifying those lost bastions of Mankind scattered across the myriad stars under the aegis of the newborn Imperium. This extraordinary undertaking would become known as the Great Crusade.
Great Crusade
The Emperor prepared extensively for the Great Crusade in the years after Unity was achieved on Terra; He created the special astro-telepath (astropath) corps to link his eventual interstellar dominion together through the use of telepathy, and engineered the creation of the Astronomican. This was a supremely powerful psychic navigational beacon powered by the Emperor's own will and psychic abilities that would allow simplified and safer interstellar travel through the Warp across far greater distances than before.
Chief amongst His designs, however, was the creation of new legions of transhuman, genetically-engineered warriors, the logical extension of the gene-troopers already under his command, though they would be far superior to the gene-enhanced troops of the Imperial Army He had used during the Unification Wars.
The Emperor first undertook the Primarch Project, the creation of 20 superhuman infants whose genomes had been designed using His own genetic code as the foundation, who were intended to mature into powerful generals and statesmen for His armies. The Primarchs would be beings of such great mental and physical superiority that nothing merely Human could stand against them.
To enhance the Primarchs beyond the capabilities that even genetic-engineering allowed, however, the Emperor also drew upon the powers of the Warp he had learned at Molech to enhance His creations, imbuing them with nearly godlike levels of charisma and capability, but also unintentionally making them susceptible to corruption by the entities of the Warp.
However, this plan went awry with the intervention of the Ruinous Powers, who feared that the Emperor's designs to unite and improve Humanity might succeed too well, vastly increasing the hold of order over the universe and diminishing their own strength. It is for this reason that all of Daemonkind refers to the Emperor as "the Anathema," the embodiment of the metaphysical opposition to Chaos.
While accounts vary as to exactly what happened, the end of the tale is always the same; the Primarchs were cast into the Warp in their gestation chambers from beneath the Himalazian (Himalaya) Mountains in the Emperor's gene-labs despite the multiple psychic wards the Emperor had laid down upon the laboratory, and thought lost.
In the aftermath of these events, the Emperor conceived a new plan. Using genetic samples that had been derived from the Primarchs' genomes, He created a caste of warriors who would possess some of the same superhuman qualities of the Primarchs and Himself. These successors to the genetically-enhanced Human warriors of the Unification Wars-era were the Legiones Astartes, the Space Marine Legions of the First Founding.
After their creation, the Emperor led the 20 Space Marine Legions, all of their Astartes originally recruited from Terran-born adolescent males, in their first missions to give them experience in war and diplomacy through the reconquest of the rest of the Sol System.
The Space Marines drove alien slavers from the moons of Saturn and Jupiter and most importantly, achieved peace and the eventual integration of Imperial Terra with the ruling Mechanicum of Mars. This crucial military and political alliance, formalised in the 30th Millennium with the signing of the Treaty of Mars, provided the Emperor with much of the technological means and materiel required to extend His crusade into the stars.
At the same time, the alliance formalised the creation of the Imperium of Man and established the Imperial bureaucracy on Terra, integrating the Mechanicum as one of the myriad organisations that comprised the newborn Adeptus Terra, the massive government of the Imperium, the future Priesthood of Earth.
With the final abatement of the Warp Storms caused by the birth-pangs of the Chaos God Slaanesh and ended by the Fall of the Aeldari, the Emperor finally began the Great Crusade in ca. 798.M30 with the campaign remembered as the First Pacification of Luna.
The Emperor's forces, concentrated amongst a rapidly growing cadre of expeditionary fleets, rediscovered long-lost Human colony worlds, cast out alien oppressors, and claimed vast new territories for the newborn Imperium to exploit across the galaxy.
Perhaps most importantly, the Emperor, leading His crusade, rediscovered His lost sons, the Primarchs, as the expeditionary fleets pushed out deeper into the depths of unexplored space. Scattered across the galaxy, the Primarchs were found one-by-one, over a period of many solar decades, and reunited with their father and their own genetic sons in the Space Marine Legions.
All were placed in command of the Astartes Legions created from their respective gene-seed and played a major part in forging their father's Imperium.
Together they brought thousands of worlds into Imperial Compliance, establishing the rule of the Imperium over these worlds and inculcating in them the values of the Imperial Truth -- a materialist, atheistic faith in reason, science and technological progress that rejected all the vestiges of Human irrationality and superstition, including all forms of religious faith.
Only by promulgating the doctrines of the Imperial Truth did the Emperor believe He could begin to weaken the hold of the need for faith and the other irrational aspects of the Human mind that birthed and sustained the power of Chaos in the Warp.
The Emperor Himself declared that Mankind would never be free to progress and advance to its destined position as the pre-eminent intelligent species in the Milky Way Galaxy until "the last stone from the last church was cast down onto the last priest."
He had already purged ancient Terra of all its ancient religions and superstitious beliefs by the time the Great Crusade began, even going so far as to personally witness the destruction of the final church on Terra's ancient soil after engaging its resident holy man, Uriah Olathaire, in a battle of ideas, wit and dogma.
The Imperial Truth also held that Humanity was the species which should rightfully rule the galaxy since its physical form was both the most pure and all of the other intelligent alien races, such as the Aeldari, had already tried and failed to maintain galaxy-spanning civilisations.
Now it was Humanity's turn to find a place amidst the stars. As almost all intelligent alien species encountered by Mankind had either proven to be irrevocably hostile to Humanity or presented a future threat to Human dominance and exploitation of the galaxy, xenos species were generally to be exterminated outright if they presented the slightest threat or obstacle to the Imperium.
The Emperor believed the Imperial Truth needed to be brought to all the worlds of Humanity, peacefully at first but imposed by war if necessary, because the Emperor believed that true unity was the only way for Humanity to survive and prosper in the face of a very hostile universe.
If this required the unfortunate use of force against those who refused to understand this necessity, then so be it. Just as He had during the Unification Wars, the Emperor again lamented the loss of innocent lives and the curtailing of individual freedoms that the fleets of the Great Crusade sometimes trod upon, but He could see no other way to safeguard Humanity and weaken the endless corruptive power of the Ruinous Powers at the same time.
While the Imperial Truth upheld the light of reason and science, it did have one unbreakable proscription: Men must never develop machines capable of true thought, what scientists had once called artificial general intelligence.
The Emperor remembered that it was the great war fought by Humanity against the thinking machines known as the Men of Iron that had helped to destroy Mankind's last united interstellar civilisation at the end of the Dark Age of Technology and He had no desire to see the Human race repeat its past mistakes.
As such, when the expeditionary fleets of the Great Crusade encountered advanced Human civilisations in the dark of space that had developed artificial general intelligences, these worlds' populations were simply exterminated outright as potential dangers to the entire body politic of the newborn Imperium.
Council of Nikaea
Additionally, there was an increasing concern as the Great Crusade progressed about the use of psychic sorcery by agents and warriors of the Imperium. The Emperor was the most powerful Human psyker to have ever lived, but He was deeply ambivalent about the growing spread of the mutant psyker genes through more and more of the Human population.
He rightly believed that most of Mankind was not yet evolved enough either physically or spiritually to truly control the great power of the Warp or avoid the corruptions and temptations offered by its more malevolent denizens. More and more often during the progress of the Imperial conquest of the galaxy, the Imperial Army and Space Marines would make planetfall only to find that the populace were in thrall to mysterious powers and unnatural mystics called "sorcerers."
These people were essentially members of Chaos Cults who would resist the forces of the Emperor with sorcerous psychic powers granted them by daemonic entities from the Warp. These psychic powers were also very akin to those used by the Thousand Sons Legion of the Primarch Magnus the Red.
The Thousand Sons had come under intense criticism for their use of sorcery by the Primarch Mortarion of the Death Guard Legion, who knew by his own personal experience with sorcerers on his homeworld of Barbarus the dangers to be found in anything spawned from the Warp, and Leman Russ of the Space Wolves Legion, for whom any battle fought through sleight of hand, clever deceit or any trick other than straight physical combat was by definition dishonorable.
Russ found the Thousand Sons' use of sorcery distasteful in the extreme. It was Russ who fought the hardest for the Imperium to ban the use of psychic powers after his own experiences during several campaigns of the Great Crusade where his Space Wolves had fought beside the Thousand Sons.
The schism grew so great that it threatened the very stability of the fledgling Imperium and so the Emperor Himself called for an Imperial conclave to resolve the issue once and for all.
Both sides of the debate over the use of psychic abilities arrived at the world of Nikaea determined to present their views, with the Emperor as the arbiter, enthroned above the dais in an ancient amphitheater that seated tens of thousands where the conclave was held.
On one side of the question were the Witch Hunters like the Sisters of Silence who presented their case by reciting a litany of Human suffering inflicted upon the Emperor's own subjects by sorcerers enslaved by what would eventually later be recognised during the Horus Heresy as Chaos, of gibbering mutants who had lost their Humanity, and of cults and power-hungry men and women who turned their psychic gifts to dark purposes. All present were also aware of the terrible damage that had been done by uncontrolled and Daemon-possessed psykers during the early days of the Age of Strife.
On the other side was a powerful advocate for the continued use of sorcery, the Primarch Magnus the Red. His very presence frightened many, but he began to speak with the great charisma that only a Primarch could wield. His argument was that no knowledge was tainted in and of itself, and no pursuit of knowledge was ever wrong so long as the seeker of that truth was the master of what he learned rather than its pawn.
He spoke with finality that his Thousand Sons Astartes had mastered their knowledge of sorcery and that there was no knowledge too labyrinthine for them to grasp or that they could not master to serve Humanity rather than enslaving it. Magnus called on the Emperor not to ban the use of psychic abilities, but to contribute to further research into their usage so that they might be harnessed more fully for the betterment of Humanity and the Imperium.
Magnus had spoken passionately with great power and the participants at the Council of Nikaea became even more divided. While they had strong arguments in their favour to justify their anti-psyker position, the Witch Hunters could not effectively match Magnus' persuasiveness. The tension could easily have been cut with a knife when a group of Space Marine Librarians approached the dais.
The Emperor acknowledged them with a nod, and all present fell silent. Among the group were some of the greatest Librarians of the Space Marine Legions. They formed a semi-circle around the dais to indicate that they spoke as one voice, but it was a young Librarian Epistolary who spoke for the group.
A psyker, he proposed, was like an athlete, a gifted individual whose native talent must be carefully nurtured. Psykers were not innately evil in themselves, but like any tool, could be used for either good or evil purposes. Sorcery, however, was the knowledge of how to wield psychic powers that had to be sought for, even bargained for with the foul entities of the Warp. No one could be truly sure who or what had benefited in the deal.
The Librarians proposed that all psykers be strictly educated by the Imperium with the express purpose of using their abilities to serve Mankind. This should become an immediate Imperial priority. The practice of sorcery would forever be outlawed as an unforgivable offense against Humanity and the worst kind of heresy.
The Council of Nikaea was also the trial of Magnus the Red -- for he was accused of sorcery and of introducing sorcerous practices to the Space Marine Legions through his lead role in the institution of the corps of Librarians. As the evidence of Magnus' continued practice of sorcery became apparent, the Emperor barely contained His wrath as He pronounced judgement on the Primarch of the Thousand Sons.
The Emperor had entrusted His son years before to obey His bidding and foreswear the use of such occult practices because of the dangers inherent to the Warp. He had entrusted only Magnus with the true secrets of the Warp to which only they remained privy, but now it appeared that His son had disobeyed His edicts and at the very least dabbled in the occult and the forbidden black arts of psychic sorcery. The confrontation between father and son is recorded in the Grimoire Hereticus.
The Emperor's judgement at the Council of Nikaea proved severe, largely as a result of His anger at Magnus. The Emperor rejected the Librarians' proposed compromise outright. With the exceptions of Navigators and Astropaths who were properly trained, controlled and sanctioned by the Imperium and were necessary to its continued existence, the Space Marine Legions were no longer to employ psykers within their ranks.
He commanded that the Primarchs were to close their Legions' Librarius departments forthwith and not to indulge the undoubted psychic talents of those Asartes who possessed the gift. All existing Space Marine Librarians were likewise forbidden to make use of their abilities and were to return to duty as line warriors.
The Council's rulings also created a new position amongst the Space Marine Legions, the Space Marine Chaplain, to uphold the Imperial Truth and help maintain the purity of an Astartes Legion's dedication and fidelity to the Emperor's commands.
The Emperor ordered Magnus once more to cease the practice of sorcery and incantation, and the pursuit of all knowledge related to magic. Magnus, of course, did not like the idea, and he remained bitterly opposed to the decision made at Nikaea. But in the end, he bent his will to his father the Emperor and agreed to obey, though the machinations of the Ruinous Powers would ultimately lead to a far darker fate for Magnus the Red and his Thousand Sons.
The Edicts of Nikaea stood largely untouched for the next 10,000 standard years as the primary Imperial policy regarding Human psychic mutation. Only the edict against the use of Librarians within the ranks of the Space Marines and later the Astra Militarum would be reversed as a result of the Horus Heresy, as that terrible civil war made clear to the rulers of the Imperium after the conflict that Astartes and other Sanctioned Psykers were essential to combat the power of the forces of Chaos.
Imperial Webway Project
Approximately two standard centuries into the Great Crusade, the Emperor decided to return to Terra to oversee a special project that He intended to cap His ambitions for Humanity. This was the secret Webway Project, in which the Emperor planned to employ the assistance of a special artefact from the Dark Age of Technology -- the Golden Throne -- that had been discovered on Terra beneath a huge and inhospitable desert on the continent of Asia.
The Emperor planned to use the Golden Throne to enter and reshape the labyrinthine dimension of the Aeldari Webway to serve as a direct and instantaneous transport network between all the worlds of the Imperium. This Human portion of the Webway would recreate the vast network of Warp Gates that had once bound together the Old Ones' and the Aeldari's ancient interstellar empires and would allow Humanity to advance at a more rapid rate, scientifically and economically, than at any other time in its history.
The Webway was a far more efficient means of travel, and most importantly bypassed the depredations of Chaos within the Warp that represented a constant hazard of death or spiritual corruption to Human faster-than-light space travel. The ultimate objective of the Webway Project was for the Emperor to completely sever Humanity from the need for the Warp in its entirety. This would further deprive Chaos of its power to corrupt and destroy and weaken the psychic emanations that powered and sustained the Chaos Gods through the protective psychic wards that shrouded every Webway corridor.
All these benefits would come as the Emperor guided His species within the protective embrace of the Webway in its evolution into a fully psychic race. This would assure its ascendancy on the galactic stage beyond what even the lost Aeldari Empire had once managed to achieve and unleash a golden age of Human civilisation unlike any before known.
A Human-dominated Webway would also truly unite the Imperium, preventing Mankind from ever again being divided by time and great distance. But this project would require all of the Emperor's considerable attention and had to be pursued in secret, lest the Aeldari or other opponents of the project learn of it and seek to stop it before His efforts could come to fruition.
The Golden Throne had been built during the Dark Age of Technology to allow Human access to the Webway and took the form of a heavily mechanised throne created from an unknown type of psychically-reactive, gold-complected alloy that was suspended over a pair of massive doors composed of the same golden alloy. These doors acted as the portal to the Webway and were supposedly large enough for a Warhound-class Scout Titan to walk through upright.
The Golden Throne was originally located in the subterranean depths of the Imperial Palace where the Emperor's gene-laboratory complex had once stood, an area known as the "Imperial Dungeon." Hundreds of red-robed Mechanicum Tech-priests and servitors toiled in the Imperial Dungeon, as the Emperor sat upon the Golden Throne and used His immense psychic powers to hold the portal into the Webway open for His workers, who constructed a new section of the labyrinth dimension intended to connect Terra to the rest of the largely abandoned transdimensional transport network.
Because the Webway had been constructed from a psychically-resistant material intended to protect it from penetration by the entities of the Warp, and Humanity did not possess the technology required to replicate it, the Emperor had to personally shield the new Human-built sections of the Webway from Warp incursions. This required him to remain on the Golden Throne continuously and was the reason why He had been forced to leave the Great Crusade in the hands of His Primarchs and return to Terra to oversee the project personally.
As such, following the extraordinary victory of Imperial forces over the greatest Ork WAAAGH! encountered by the Imperium to that time during the Ullanor Crusade, the Emperor decided that He was no longer directly needed to command the efforts of the Great Crusade. To this end, the Emperor placed Horus, His favoured and most talented son, in charge of the military advancement of the Great Crusade in His stead.
Horus was foremost amongst the Primarchs and was the first re-discovered by the Emperor on the dying world of Cthonia that lay so close to Terra that Warp-Drive was not needed to reach the planet. Horus was the only Primarch to serve in the Great Crusade alongside his father for many solar decades and was the most highly honoured of the Emperor's sons, the Primarch he most trusted and most loved.
The two had fought together at the forefront of the early Great Crusade. The Emperor had protected Horus during the Siege of Reillis while Horus repaid the favor during the Battle of Gorro. During the Battle of Gyros-Thravian, the Emperor slew the mighty Ork Warboss Gharkul Blackfang after it had held off three of his Primarchs.
With such a history between them, the Emperor felt Horus was the man to lead the Great Crusade in His absence. Granting Horus the unique title and rank of Warmaster, the Emperor declared that the time had come for His sons to show Him what great leaders they were. Turning His back on direct military matters, the Emperor created the Council of Terra (the precursor of the Senatorum Imperialis), the Imperial Tithe, and expanded the civil governing and bureaucratic bodies of the Imperium like the Adeptus Administratum, before retiring in seclusion beneath the Imperial Palace to begin work upon the Golden Throne and the Webway Project.
But the Emperor's decision to not tell His sons why He had retired to Terra as well as His decision to begin shifting the Imperium's government out of the direct control of the Primarchs on the War Council and to the Terran nobility and bureaucrats whom they detested sowed the seeds of discord among the Primarchs. So, too, did disquiet over the Emperor's decision to raise Horus above his brothers by naming him the Warmaster and thus their commanding officer.
From these seeds of ambition, pride and jealousy the Chaos Gods would find fertile ground to corrupt many of the Primarchs and bring on the horrors of the Horus Heresy.
Horus Heresy
This turn of events did not please all of the Emperor's subjects, several of His Primarch sons in particular. In the final stages of the Great Crusade, the Emperor's most trusted son Horus succumbed to the temptations of Chaos. This seduction had been set in place over long decades by the Primarch Lorgar and his Word Bearers Legion.
The idea of "the Pilgrimage," a journey to the legendary place where mortals could directly interact with the gods, was an ancient mythological trope on many Human-settled worlds of the Milky Way Galaxy, including Lorgar and the Word Bearers' homeworld of Colchis. Of course, such a place, the Warp, did exist, and one could discover the Primordial Truth of the universe there, i.e. that the Immaterium was dominated by the powerful psychic entities known as the Chaos Gods.
Prompted by the so-called "Pilgrimage of Lorgar" to discover whether or not the gods once worshipped by the adherents of the Old Faith of Colchis actually existed, Lorgar journeyed with the Word Bearers Legion's Serrated Sun Chapter to what was then the fringes of known Imperial space as part of the 1301st Expeditionary Fleet of the Great Crusade.
At this time, Lorgar had not yet fallen to the corruption of Chaos, though he had turned against the Emperor of Mankind as a deity no longer worthy of his worship after the Emperor and the Ultramarines had personally humiliated him and the entire Word Bearers Legion on the world of Khur 43 Terran years before the start of the Horus Heresy.
The Emperor had come to Khur personally with His Regent, Malcador the Sigillite, after ordering the Ultramarines to destroy the Khurian city of Monarchia where the Emperor was worshipped as a god as a result of the teachings of the Word Bearers. He made his displeasure known to Lorgar about the Word Bearers spreading the religion of Emperor-worship to every world they brought into the Imperium, in direct contravention of the atheist philosophy of the Imperial Truth.
The Emperor forced the entire Legion to kneel against their will through the use of His psychic might and then explained that they were the only Astartes Legion to have failed His purpose during the Great Crusade. After this humiliation, Lorgar, on the advice of his First Captain Kor Phaeron and the Word Bearers' First Chaplain Erebus, both already corrupted by Chaos, decided to undertake a pilgrimage to discover if the gods worshipped by the ancient Old Faith of Colchis were real and worthy of the Word Bearers' faith and allegiance.
Lorgar believed that the Emperor was wrong to condemn Humanity's natural instinct to seek out the divine as an unworthy superstition and he intended to discover if there were truly deities worthy of Mankind's respect. To this end, though Lorgar no longer had any love or loyalty for the Emperor, he and his XVII Legion rejoined the Great Crusade but did so only for their efforts to serve as a front for their pursuit of the pilgrimage.
The Word Bearers were also accompanied on this pilgrimage by 5 members of the Legio Custodes who had been set by the Emperor to watch over everything the Word Bearers did to prevent them from falling back into error. The Word Bearers' pursuit of any scrap of information that could be found on the Primordial Truth or the nature of the place where gods and mortals could mingle ultimately led the 1301st Expeditionary Fleet to the Cadia System near the largest Warp Storm in the universe, later known to the Imperium as the Eye of Terror.
The expeditionary fleet's master of astropaths advised Lorgar that unusual "voices" in the Warp were heard in the vicinity of the great Warp rift, voices that spoke directly to the Primarch as well, which were the voices of the Chaos entities within the Immaterium.
It would be in the Cadia System that Lorgar would learn that his suspicions had been correct and that all of the religions across the galaxy that possessed so many similarities to the Colchisian Old Faith were not coincidences, but expressions of worship in the universal truth that was the existence of Chaos.
The decision was made to hold orbit over Cadia and for the 1301st Fleet's elements to make planetfall on the unknown world, designated as 1301-12. The landing force was comprised of Imperial Army, Word Bearers, Legio Custodes and Legio Cybernetica elements. The landing party, led by Lorgar, was greeted by a large number of barbaric Human tribes, tribes described as "dressed in rags and wielding spears tipped by flint blades...yet they showed little fear." Most notable were the barbarians' purple eyes, which reflected the colour of the Eye of Terror itself in the spectrum of visible light.
Despite the Custodian Vendatha's protests and request to execute the heathens, the Word Bearers approached the natives. A strange woman emerged from the crowd and addressed the Primarch directly, calling him by name as Lorgar Aurelian and welcoming him to Cadia.
This woman, the Chaos priestess Ingethel of Cadia, would ultimately lead the Primarch down a path of spiritual enlightenment that actually marked the beginning of Lorgar's fall to heresy and Chaos. Later, Ingethel would initiate a ritual that would see her transformed into the Daemon Prince known as Ingethel the Ascended, and then lead the 1301st Fleet's scout vessel Orfeo's Lament into the Eye of Terror.
Within the Eye of Terror, the Serrated Sun Chapter of the Word Bearers Legion witnessed the failure of the ancient Aeldari Empire first-hand in the form of the Crone Worlds that had been scoured of all life that littered the Eye's region of space. Ingethel, of course, lied to the Word Bearers about how the Chaos God Slaanesh had truly been born and warned that the Aeldari had failed as a species and suffered the Fall because at the moment of their ascension they were unable to accept the Primordial Truth, i.e. worship Chaos.
They gave birth to a god of pleasure, yet they had felt no joy at her coming. Their new god, Slaanesh, had awoken to consciousness in the 29st Millennium to find its worshippers abandoning it out of ignorance and fear, and from the Prince of Pleasure's grief was born the endless storm of the Great Eye (the Eye of Terror), an echo of the birth-screams of the Aeldari's new and rejected god.
The nature of the Primordial Truth was revealed to the Word Bearers in the ashes of the Aeldari Empire, and Ingethel warned them that in order for Humanity as a species to survive they must not commit the same sins the Aeldari did, and must instead accept the worship of Chaos.
The surviving Space Marines of the Word Bearers' Serrated Sun Chapter eventually returned to Cadia and related to Lorgar all that had happened and all that they had learned within the Eye, the true place where mortals and gods could meet. Following his own subsequent visit into the Eye of Terror and his acceptance by the Chaos Gods as their new mortal champion, Lorgar ordered a cyclonic bombardment of the planet. This wiped out the original Cadians and left the planet abandoned so that no others could stumble upon the secret of the Primordial Truth that had been entrusted to him alone by the Chaos Gods.
However, the planet's extremely strategic location meant that it would prove useful to the Imperium and in the 32nd Millennium Imperial colonists were despatched to resettle the world, becoming the ancestors of the later population of Cadians. Perhaps as a result of the Eye of Terror's proximity, this later population of Cadians also soon developed the unusual violet-coloured eyes that had marked the first Human inhabitants of the planet.
This "truth" of Chaos' existence changed Lorgar and the Word Bearers forever as they were exposed to the Ruinous Powers of Chaos and slowly corrupted, the first of the Legiones Astartes to worship the Chaos Gods and become Traitors to the Emperor in their hearts.
Lorgar and the Word Bearers spent the remaining years of the Great Crusade attempting to enlighten Humanity about the true spiritual nature of Creation, ultimately resorting to manipulation and deception to sway nine of the Primarchs to the cause of Chaos as their gods demanded, the most notable being the Warmaster Horus. When it became clear that Humanity could not be enlightened by Chaos without first being forcibly weaned at a great price in blood from the Emperor's false Imperial Truth, Lorgar willingly helped orchestrate the events of the Horus Heresy itself.
To this end, Lorgar used his Legion's First Chaplain Erebus as his agent. Erebus stole a Chaos-infected blade known as a Kinebrach Anathame from the branch of Humanity called the Interex during the Luna Wolves' brief contact with that technologically-advanced offshoot of Mankind.
When Horus and the Luna Wolves personally arrived on the moon of the world of Davin to put down a rebellion against Imperial authority led by the former Planetary Governor Eugen Temba, Erebus made sure that the Anathame ended up in Temba's hands where he could use it to wound Horus. Temba had become a servant of the Plague Lord Nurgle and the moon of Davin was a decaying swamp filled with undead horrors like Plague Zombies created from Temba's Imperial Army garrison who caused Horus and the Luna Wolves no small amount of grief.
In a final confrontation on the bridge of his downed Imperial warship, Horus slew the vile Nurglite, but not before the Anathame bit deep into his flesh and delivered a toxin personally created by the Plague Lord, a poison so powerful that not even the Primarch's enhanced, superhuman immune system could successfully fight it off. In desperation, the Luna Wolves allowed Erebus to take Horus to the Davinite Lodge Priests of the Temple of the Serpent Lodge, a temple dedicated to Chaos on Davin, who promised that they could heal the Warmaster.
During his "healing," the Warmaster's spirit was actually sent into the Immaterium to meet with the Ruinous Powers with Erebus as his guide. Drawing on the Primarch's own untapped subconscious wells of ambition and jealousy over his father's seeming abandonment, Horus was shown a vision granted by the Ruinous Powers.
This falsely revealed that the reason the Emperor had left the Great Crusade and returned to Terra was so that He could attempt to reach godhood, abandon all His sons and betray the Imperial Truth's promise to enlighten Humanity and free it from the shackles of false gods and organised religion.
Believing this vision of the future, which ironically was actually a vision of the Imperium that would only come to pass because of his betrayal of the Emperor, Horus saw it as his duty to save the Imperium of Man from such a fate and turned on his father. He accepted the assistance of the Ruinous Powers in their guise of Chaos Undivided in return for his rebellion against the Emperor.
Having corrupted fully half of the Space Marine Legions to the service of Chaos, Horus then led them against the Emperor and plunged the fledgling galactic empire into a colossal civil war that lasted for 7 standard years and began with the terrible betrayals of the Loyalist forces during the Battles of Istvaan III and Istvaan V.
This conflict, known to later generations as the Horus Heresy, became the most terrible in Human history, and billions perished as the Traitor Legions tore apart the empire they had helped to forge. The climax of the conflict came during the Siege of Terra, when the Traitor Legions and the other forces of Chaos that they led unsuccessfully assaulted the heart of the Imperial Palace itself.
Unable to breach the Inner Palace and the throne room of the Emperor due to the sacrifice of countless Loyalist Astartes and the victory of the Primarch Sanguinius over the Bloodthirster Greater Daemon Ka'Bandha, Horus feared that his forces were running out of time as Loyalist reinforcements moved to reach Terra and relieve their compatriots. Hoping to force a final confrontation that would decide the course of the war once and for all, Horus deliberately dropped the Void Shields surrounding his flagship, the Vengeful Spirit, which stood in orbit above the Imperial Throneworld.
Throughout all the course of the Horus Heresy, the Emperor had been forced to remain on the mechanism of the Golden Throne. At the start of the Horus Heresy, the Primarch Magnus the Red had violated the Edicts of Nikaea to use sorcery to penetrate the psychic wards of the Imperial Palace and bring news of Horus' treachery directly to the Emperor.
The Emperor had refused to believe Magnus' warning about His favoured son and instead came to believe that it was Magnus who had been corrupted by Chaos because of his decision to continue to use sorcery in violation of Imperial law.
The Emperor had despatched Leman Russ and his Space Wolves Legion to bring Magnus back to Terra to account for his actions, but Horus tampered with the Emperor's orders. Horus' message to the Wolf King so enraged Leman Russ against his sorcerous brother that he ordered the Space Wolves to launch an all-out assault on the Thousand Sons Legion's homeworld of Prospero.
This assault, remembered as the Fall of Prospero in 004.M31, ultimately led to the fall of the Thousand Sons and Magnus to the service of the Chaos God Tzeentch in order to save both themselves and all the knowledge they had collected over the centuries.
At the same time, Magnus' spell to penetrate the Imperial Palace's psychic wards had also badly damaged the Webway Project, allowing hordes of Daemons to gleefully punch through the Emperor's weakened psychic shield and assault the thousands of Mechanicum workers constructing the Human portions of the Webway.
The Legio Custodes and the Sisters of Silence were forced to fight a desperate battle to prevent the Daemons from pouring through the portal generated by the Golden Throne and into the dungeon of the Imperial Palace itself. While the Imperial forces were ultimately successful in fighting back the daemonic assault, only the Emperor was psychically powerful enough to keep the portal closed and the Daemons trapped within the Human-constructed Webway.
With His attentions consumed by this crisis, the Emperor left the management of Horus' rebellion to Malcador the Sigillite and the Primarch Rogal Dorn of the Imperial Fists Legion. During this time, the Emperor engaged in telepathic communications with the low-ranked Astropath Kai Zulane, who had been granted a precognitive vision of the Horus Heresy's conclusion and the Emperor's terrible fate at the hands of his best-loved son. During their psychic communications, the Emperor revealed He not only had already known what His ultimate fate would be, but had come to accept it as the price of the failure of His ambitions for Humanity.
Later Corvus Corax, the Primarch of the Raven Guard Legion, deeply distraught over the almost complete annihilation of his Legion during the Drop Site Massacre on Istvaan V, came to the Imperial Palace and demanded an audience with the Emperor. Diverting some of his attention from the strenuous task of maintaining the psychic defences of Terra from the breach in the Webway, the Emperor telepathically imbued the secrets of creating Astartes into his son's mind.
Corax then began rebuilding the Raven Guard using these techniques to rapidly accelerate Astartes development, though his efforts were ultimately corrupted by the insidious actions of the Alpha Legion. The Raven Guard would remain one of the so-called Shattered Legions throughout the rest of the Heresy and would play little further part in its outcome.
After five standard years of protecting the Human homeworld from the consequences of Magnus' Webway breach while seated on the Golden Throne, the Emperor began to exhibit the first signs of physical fatigue. As the psychic strain worsened, His nose would sometimes bleed, and this image would be projected even in the telepathic visions he sent to his Legio Custodes Custodian Tribune Ra Endymion.
After sensing the birth of the powerful daemon Drach'nyen in the Warp, the Emperor knew the War Within the Webway was reaching its climax and the ultimate fate of Humanity would soon be decided. He ordered the Sisters of Silence to gather a thousand psykers across the galaxy and sacrifice them to the Golden Throne.
This allowed the device to be powered for a single solar day without the Emperor's presence, and he used that time to plunge into the Webway and rescue the retreating Imperial forces. After sweeping aside the daemonic hordes, He confronted Drach'nyen and sealed it into the body of Ra Endymion, telling his loyal Custodian to run as far as he could into the depths of the Webway in order to keep Humanity safe from the Daemon's influence.
Afterwards the Emperor was forced to seal the Webway portal on Terra by again becoming a prisoner to the operation of the Golden Throne. The Emperor lamented to His followers that His great work was ruined and maintained that now that the Webway Project had failed to become a reality, Humanity was doomed to the same fate as the Aeldari, ultimate extinction at the hands of the forces of Chaos.
Though the Emperor already knew through his prescient visions that Horus would be defeated at His hands, another Chaos Lord would soon take his place as the Warmaster of Chaos and seek to continue his mission to destroy the Imperium.
To the shock of his Custodian Diocletian Coros, the Emperor declared the Imperium of Man to ultimately be doomed, whether it was in a single standard year or ten thousand, and for the first time admitted that even He did not know what to do to save Mankind from extinction.
As a result, as the Horus Heresy reached its climax with the Traitors' assault on Terra itself seven standard years after the start of the Warmaster's drive on the Throneworld, the Emperor was forced to remain on the Golden Throne at all times save for the few moments when Malcador the Sigillite, the Regent of Terra and the second strongest Human psyker, could take His place.
When the Emperor learned of Horus' action in lowering his flagship the Vengeful Spirit's Void Shields during the final hours of the Siege of Terra, He realised that His treacherous son was actually offering an invitation to battle. The Emperor believed He had to take the war to Horus to put an end to the terrible conflict once and for all.
He had Malcador the Sigillite take His place upon the Golden Throne to protect Terra from a daemonic assault through the Imperial Webway portal that lay below the throne and prepared a strike team of Astartes to face the Warmaster on his own ground. The last act of the bloody treachery of the Horus Heresy was played out above Terra, as the Emperor led a desperate assault of Imperial Fists and Blood Angels Space Marines against Horus' Chaos-corrupted flagship, using teleporter technology to make their way aboard.
The Primarch Sanguinius also accompanied the assault force, but the Warmaster's command over the powers of Chaos caused the attackers to be split up and teleported to random locations throughout the massive warship. Sanguinius reached Horus first and met him in a mighty battle that resulted in his own death at his brother's hands, but not before the angelic Primarch managed to create a small gap in the Warmaster's Terminator Armour. The Emperor eventually managed to make His way to the Battle Barge's bridge.
Though the Emperor was a being of unfathomable psychic and physical might, Horus had become a being of monstrous strength, bloated with the combined powers of all four Chaos Gods, the true champion of Chaos Undivided, even as the Emperor remained the galaxy's ultimate champion of order.
The two champions engaged one another in a tragic battle of father and son, as Horus mortally wounded the Emperor, tearing off one of His arms and shattering His internal organs, largely because the Emperor still loved Horus and could not bring Himself to use the full extent of His psychic abilities to destroy His son.
At the critical point in the battle, a lone Legio Custodes warrior who had accompanied the Emperor entered the battleship's bridge, having successfully caught up to his master. Horus flayed him alive with but a look using the potent powers of Chaos sorcery that he now commanded.
In that instant of Horus' pure cruelty and casual disregard for Human life, the Emperor finally realised how truly far His favoured son had fallen into the grip of the Ruinous Powers and how Humanity would suffer and ultimately be destroyed under his rule. The sacrifice of the Custodian bought the Emperor the time He needed to deliver a finishing blow to Horus.
With iron resolve, He gathered the full strength of His mind at last and delivered a massive psychic attack through the chink in Warmaster's Terminator Armour that killed Horus almost instantly and obliterated his very soul from the Warp so that the Chaos Gods could not resurrect their champion.
In his final moments before the Emperor unleashed His final attack to blot Horus' soul from existence, the corrupting powers of Chaos briefly relinquished their hold on the Warmaster's soul and the Emperor sensed the retur
