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Warhammer 40K: The Cyclops Of Chaos, The Crimson King – Magnus The Red

12 Minute Read
Jun 21 2022

Today we speak of the mighty Lord of the Thousand Sons – Magnus the Red, the mightiest living psyker in the galaxy.

Magnus the Red (Also known as the Crimson King, the Sorcerer-King, Cyclopean Magnus or the Red Cyclops) is the Primarch of the Thousand Sons Chaos Space Marine legion. A giant in both physical and mental terms whilst a mortal inhabitant of the materium, Magnus long tried to understand and control the warp, becoming a sorcerer of formidable power. Magnus would eventually fall from favor with his father, the Emperor, and with the majority of his brother-primarchs due to his zealous advocacy and use of such power.

Early Life

Magnus, as an infant, was dropped onto the remote colony world of Prospero. Magnus was unique among his brothers as he was entirely aware of his own birth and development, and remembers his infancy completely. He also regularly communed with the Emperor via telepathy before their official reunion.Magnus was incredibly fortunate to land on Prospero, as anywhere else his psychic nature would have made him an outcast, shunned and hunted. Prospero was a world of outcast human psykers, making him nothing special in the eyes of the colonists. They had chosen Prospero for its remoteness from Terra. When Magnus fell from the skies, it was like a portentous comet. His pod landed in the central plaza of all the places on the planet.

Mentored by the fame psyker-scholar Amon, he became a ward of the scholars and quickly gained their powers, surpassing them in many ways. Magnus soon even eclipsed Amon in power.Magnus mastered every psychic training program and soon surpassed the greatest adepts of the commune. By that time he had so much control of his psychic powers, he was by far the greatest person on the planet. One day, Magnus performed something to change the world forever. Instead of channeling Warp energy from the Warp to the Materium universe, he looked into the Warp, going from the student to absolute master instantly. Magnus became the hero of Prospero when he led a campaign to purge the Psychneuein from Prospero, who for centuries had wreaked havoc on the planets population. With the threat removed, Magnus rebuilt many of Prospero’s cities, most notably Tizca, which became renowned for its beauty and splendor. The chief scholars of Prospero that survived the war with the Psycheuein became the founders of the Cults of the Thousand Sons.

Discovery by The Emperor

With such a mind in the Warp, it was not long until the Emperor noticed him. When his fleet arrived and the Emperor stepped foot upon the planet, he and Magnus immediately embraced and conversed as if the two had known each other for years; as indeed they may have done, in the mind if not in the flesh.

The Thousand Sons Magnus inherited were rife with psychic mutations, being based on Magnus’s genes. He took them in as his own and began training them in the ways of the psyker. Individuals from within the Imperium who were fearful of these rampant mutations began to voice their opinions openly, but Magnus silenced them. Magnus and the Emperor formed a seemingly close bond, reaching into the Warp together. However despite the warnings of his Father to beware the horrors of the Empyrean, Magnus lost his right eye in a failed bargain with (what he would later discover to be) Tzeentch to save his legions sons from mutation. The bargain cost Magnus his eye, but for a time the mutations did go into remission.

Magnus fought bravely and successfully during the Great Crusade and become close to Horus, Lorgar, and Jaghatai Khan but he was always a wild and impetuous commander. Due to his early brush with Chaos during his abduction, Magnus had an inherent affinity for the Warp and the secrets within its fabric. Throughout the Crusade he came into contact with long isolated cultures where psychics had been allowed to flourish. Although warned by the Emperor to shun such matters, Magnus began to gather arcane lore from across the galaxy. From this material he compiled the monumental tome of sorcery that would come to be called the Book of Magnus.


The further from Terra the crusade went, the more strange warp-influenced creatures they came across. This naturally made Magnus look bad, his control of the Warp being similar to these creatures. Leman Russ and Mortarion both distrusted Magnus due to his use of the Warp and because of his use of deceit where they would have used more straightforward physical strength. Such was the distrust that Magnus and Russ almost came to blows on Ark Reach Secundus over the fate of the planets Great Library, and heavy bloodshed was only prevented by the intervention of Lorgar. To solve this dispute, the Emperor called for a debate on the use of psychic powers. They gathered on Nikaea and the Emperor presided over the debate. The Emperor finally ruled that only astropaths and Navigators would be tolerated, the Librariums were to be disbanded, and that sorcery was to be banned. Magnus was not pleased with the outcome. Nonetheless he remained true to the Imperium, and tried to dissuade his friend and brother Lorgar from attempting to discover the secrets of the Warp for fear that it may corrupt him.


The Horus Heresy

Magnus returned to Prospero, intent on pursuing his sorcerous experiments in secrecy. He peered into the Warp, and saw a vision of Horus’ revolt and roles all the legions would play, except his own. Entering the mind of his brother while it was under a Chaos ritual initiated by Erebus and Cultists on Davin, Magnus attempted to persuade his brother away from heresy and remain loyal to their father. However when that failed, Magnus decided to warn the Emperor via an astral projection spell rather than the much slower mode of astropathy. As his disembodied spirit blazed through the Warp, he came across a Webway corridor that led to Terra.

Unbeknownst to him, this particular corridor was constructed by humans, a part of the Emperor’s secret Webway project. Magnus tried in vain to breach the wall of the corridor, but then an anonymous voice from within the Warp offered Magnus the extra power he needed, and the overconfident Magnus accepted without question. Magnus tore a breach in the wall and followed the corridor to Terra, bursting through the portal beneath the Golden Throne. The breach allowed daemons to invade the Webway and ruin the Emperor’s project. Magnus was so shaken and horrified by his blunder that he could not find the will to deliver his warning, and instead retreated back to his physical body on Prospero.

The Emperor dispatched Leman Russ and his Space Wolves to arrest Magnus and bring him to Terra. On the way to Prospero, Leman Russ received new orders from the now-corrupted Horus who changed the order to read that the Emperor had changed his mind and wished the Thousand Sons destroyed. In the ensuing Burning of Prospero, Magnus watched in horror as the great libraries and arcane archives he had worked so hard to create were burned to the ground. Engaging Leman Russ in combat, just as the Space Wolves Primarch was about to strike the final blow, Magnus and his forces disappeared into the Warp thanks to a ritual he had helped prepare with Ahriman. There, Magnus found what he had wanted: unrestricted psychic powers and an opportunity for vengeance. Eventually giving himself to the forces of Chaos, Magnus took all that he had from Prospero, from the Imperium, into the Warp forever. Magnus’ physical form had been destroyed in battle against Russ, and now existed as a being of corporeal Warp energy in the Eye of Terror alongside his legion. However, in truth he had been shattered into many shards which acted independently of the other.



 The Shards of Magnus

One of these shards of Magnus later appeared as an ethereal projection on the ruins of Prospero to Jaghatai Khan and told his brother it was time to finally choose a side in the conflict. A shard of Magnus again appeared on board the Salamanders Battle Barge Charybdis, this time as a mental projection. There, Magnus conversed with Captain Artellus Numeon, asking him what he would sacrifice to see Vulkan restored and seemingly helping the ship through the Ruinstorm. Magnus’ words to Numeon eventually were the catalyst for the Salamanders Captain to sacrifice himself to resurrect Vulkan.

The main form of Magnus resided on the Planet of Sorcerers, but he was deteriorating. Ahriman left to track down the shards that he could find, being given a vague location of five shards after Amon temporarily transformed into the primarch on the ruins of Prospero. Eventually, Ahriman was able to recover four, which allowed Magnus to restore much of his lost power and prevent his deterioration into nothingness. The fifth, representing Magnus’ goodness and humanity, was located on Terra, and he notified his legionaries that they would join Horus in order to free it and restore himself to his original form. Magnus later reappeared at the head of an army of Thousand Sons on Ullanor, answering Horus’ call to muster there in preparation for the drive on Terra. Shortly before the Siege of Terra Magnus and Ahriman journeyed to the ruins of Prospero in order to recover the Daemon Shai-Tan to use against the Emperor’s psychic shielding of Terra.

Siege of Terra

Magnus eventually joined forces with the Traitor Astartes led by Horus, taking part in the Siege of Terra as vengeance against the Emperor for betraying him. In the early stages of the Siege he appeared in the traitor war council aboard the Vengeful Spirit, advising on how to disable the Emperor’s psychic barrier that prevented the manifestation of Daemons upon Terra. After the fall of the Lion’s Gate Spaceport rumors began to swirl that Magnus had finally been cited on the field and Malcador believed he was committing his psychic might to weaken the Emperor. During the assault on the Colossi Gate Magnus met with his fallen brother Mortarion, sympathizing with the constant pain the Death Lord was in. Magnus taught Mortarion to better control his Warp powers, helping the Death Guard Primarch regain a measure of his old composure. In truth, Magnus simply did this in order to manipulate Mortarion into launching an attack to cover his infiltration of the Imperial Dungeon. Later when the Thousand Sons and Death Guard attack on the Colossi Gate fails, Magnus says the operation wasn’t a total failure as he had gotten what he wanted.

Shortly after the defeat of the traitors at the Saturnine Wall Magnus made his move, assembling all 9,000 Thousand Sons on Terra for an attack on the Western Hemispheric region of the Palace. During the battle Magnus’ forces achieved a breach after Magnus himself entered the fray and hurled the dying Capitol Imperialis Khasisatra into the Palace walls.  However this was just a ruse by Magnus, who used the chaos to infiltrate into the Sanctum Imperialis alongside Ahriman, Menkaura, Amon, and Atrahasis. Psychically cloaking themselves as Blood Angels, Magnus and his entourage moved through the Great Observatory. After infiltrating deep beneath the Palace via the Hall of Leng, Magnus and his sons came before Malcador and Alivia Sureka at the shore of a great underground lake. Malcador bid Magnus to play a game of regicide with Sureka, and it soon became apparent he was attempting to turn the Crimson King to his cause. However when Malcador revealed the lost shard of Magnus on Terra was now out of his reach (having since been implanted into Janus) the Primarch became enraged and seemingly killed Malcador. Though visibly shaken by what he had done in his rage, Magnus nonetheless decided to move into the Imperial Throne Room and kill the Emperor.

Determining to go through with his vow to slay his father, Magnus powered up his staff to deliver a killing blow to the Emperor upon the Golden Throne. However before he could carry through with the act he was blocked by Vulkan as his Thousand Sons engaged in battle with Vulkan’s Draakward and Bjarki’s pack. The Emperor’s eyes suddenly opened, and Magnus found himself floating through the ether with his father and witnessing the rise and fall of the galaxy’s many empires. The Emperor showed Magnus a future where the Primarchs never turned against the Imperium and the last world in the galaxy was conquered in the name of mankind. In this future Magnus sat upon the Golden Throne to power the Imperial Webway, but his soul was in perpetual bliss as it drifted in the immaterium along the Emperor to discover the limits of cosmic knowledge.

The Emperor stated that this future may yet happen, and Magnus could return to the loyalists side at the head of a new legion being prepared for him. Together, the Emperor and Magnus would expel the traitors from Terra and undertake the Great Scouring. However the price was steep, for the Emperor declared the Thousand Sons damned due to rampant flesh change. They could not follow Magnus back into the Emperor’s embrace, and would need to be purged. This price was too much for Magnus to bear, and he again struck at the Emperor but found himself in battle with Vulkan. During the battle Magnus nearly defeated the Salamanders Primarch, but the sacrifice of Barek Zytos allowed Vulkan to seemingly pummel the Crimson King into submission. Before Vulkan could deliver the final blow Magnus finally gave himself wholly to the powers of Chaos, ascending to a new etheric form and being expelled by the anti-Daemonic wards of the Imperial Dungeon alongside his sons. Magnus was now fully committed to the traitor cause.


After the Horus Heresy

After the failure of the Horus Heresy, the newly-formed commune joined together with Ahriman to find a way to stop the mutation caused by their allegiance to Tzeentch. They cast a mighty spell to counter the corruption. The Planet of Sorcerers, the new world of the Thousand Sons, was arcing with violent blue and yellow streaks of lightning. They would strike down every Marine until Magnus had to intervene. Their mutations had been halted, but at a terrible cost: their bodies turned to dust and their armour sealed tightly shut.

Magnus summoned Ahriman and his council, and railed at them for what they had done. When Ahriman protested, Magnus fought and gained the upper hand. Ahriman, no match for his Primarch, was struck down. But just as Magnus raised his fist to kill him, Tzeentch itself spoke: “Magnus, you would destroy my pawns so readily?” then Magnus knew that his master had planned for all of this. So he spared Ahriman and banished him and his council on an eternal quest to understand Tzeentch. They still wander the galaxy, looking for relics of a former time of psychic prowess and control. It is said that Ahriman even attempted to access the Eldar webways, although this is unconfirmed

Despite knowing Tzeentch’s plans had led to this fate, Magnus was beyond enraged to see that the Legion he had sacrificed so much for, his legion of scholars, had been reduced to automatons who could no longer even think. With his homeworld lost and his legion in ruin, Magnus ascended to the top of his tower and vowed, as Horus had, that he would see the galaxy burn.

Later, seeking revenge against the Space Wolves for the Burning of Prospero, Magnus would lead his Thousand Sons in an assault against the Space Wolves homeworld of Fenris in what became known as the Battle of the Fang.

In the many years since the Heresy, Magnus has become increasingly aloof and detached from his legion and the happenings of the Materium. He spends much of his time in the Warp, waging the Great Game of the Dark Gods.

Sometime later in the 41st Millennium, Ahriman attempted to cast his second Rubric on the Planet of the Sorcerers to cure his Legion. However a rival group of Thousand Sons Sorcerers discovered the Rubric would result in the destruction of Magnus, and the Primarch ended up hijacking the ritual to assimilate with even more lost shards of himself. Magnus became near-complete, but the shards that were lost were those that represented his most noble qualities.

Abilities and Wargear

Magnus was above all else a supremely powerful Psyker matched in the Imperium only by Malcador and surpassed only by the Emperor. Magnus was capable of changing his size and form at will, dispatching scores of enemies simultaneously with psychic assaults, and single-handily battling Titans. His psychic foresight allowed him to predict and foresee most events. Magnus’ power was such that it was speculated that the Emperor intended to use him to power the Golden Throne, a task that quickly killed even Malcador. Magnus’ own appearance is a byproduct of his psychic power, with Lorgar stating that nobody has ever seen his true form.

Magnus usually relied on his immense psychic power for battle, but was equipped with regular weaponry. He was typically seen wielding a massive Chain Weapon shaped as a Khopesh and a large Bolt Pistol. He wore an ornate suit of Power Armour with many engravings and wardings.


Learn more about the Thousand Sons Legion

“But all things change, my brother. I’m not the same as I was, and you’re… well, let us not mention where you are now.”

– Magnus the Red to a statue of Leman Russ, during the Battle of the Fang

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