At the same moment the Void Sword was leading its fleet across the stars to test its weaponry, the Emperor's Key in Axion's grasp finally elicited a new response within the Sol System's Webway.
The crystal within the key pulsed with a burgeoning radiance, casting dots of brilliance that connected into a luminous, pale-gold line. This thread of light stretched continuously along the lightless depths of the Webway, carving a path through the gloom. The mechanical legions saturating the labyrinthine dimension immediately identified the sector where the corresponding shift had occurred.
A towering runic portal suddenly manifested within their visual arrays.
The massive gate stood ten meters high, its surface engraved with intricate, ornamental tableaus. At the center of the threshold sat the Aquila of the Imperium, its edges bordered by countless peculiar runes. Previously, innumerable mechanical units had patrolled this exact coordinate, finding nothing but a blank expanse of Webway wall.
Axion, remote-controlling a physical frame, soon arrived before the colossal doors. The key in his hand released a soft, golden glow. On the great gates, a runic array, infused with a distinct mechanical aesthetic, began to rotate slightly.
With a heavy, muffled thud, the locks disengaged.
The doors slowly swung inward, revealing a chamber of modest dimensions. The space felt cramped, crowded with strangely shaped instruments and apparatuses. In a corner where machinery overlapped, sat a massive workbench.
Axion stepped inside, maneuvering past a multitude of devices with unknown functions. He reached the workbench and carefully cross-referenced the dimensions of the Emperor's skeletal remains recorded within his core. After simulating the approximate proportions of the Master of Mankind's living physical form, it was easy to confirm that this was indeed the Emperor's personal desk.
The desk was a clutter of handwritten data and manually sketched runic schematics. These were the findings and structural designs produced by the Emperor during the construction of the Imperial Webway.
The Webway system itself was not the Emperor's creation; it was the legacy of the Old Ones, those who had originally engineered the Aeldari and the Orks. The Emperor's contribution had been the construction of a brief, entirely new segment of Webway, which he then attempted to graft onto the Old Ones' existing network. While the Aeldari could establish Webway Gates within existing sectors, they possessed almost no capacity to construct new extensions.
Yet, the Emperor had achieved this feat.
Furthermore, he was not satisfied with mere connectivity. He had not only reinforced his artificial Webway with additional psychic shielding and cloaking arrays but had established this secret laboratory at the junction of his artificial path and the ancestral tunnels of the Old Ones. His objective was nothing less than the decryption of the Old Ones' control systems, seeking total mastery over the entire Webway network.
However, just as his research neared completion and the connection experiments began, the Horus Heresy erupted.
In his desperate bid to warn the Emperor of Horus's treachery, Magnus the Red unleashed a psychic talent that rivaled the Emperor's own. A colossal surge of psychic power lanced from the Warp directly toward Terra, shattering the Emperor's ultimate vision for humanity's salvation, a future where they could navigate the stars without the perils of the Empyrean.
Under the impact of Magnus's psychic message, the protective aegis of the artificial Webway was torn to shreds. Unbeknownst to Magnus, the power that had allowed him to reach the Emperor had been granted by Tzeentch. As the personification of guile, the Architect of Fate knew that a sea of daemons, drawn by the light of the Astronomican, had already amassed within the ancient Webway tunnels. The moment the psychic barriers failed, they flooded into this new artery that led straight to the heart of the Throneworld.
Faced with this daemonic onslaught, the Emperor was forced to abandon his experiments and lead the Imperial forces within the Webway to repel the neverborn. Following the conclusion of the Webway War, the Emperor commanded Leman Russ to bring Magnus back to Terra to face judgment for the Thousand Sons Legion and the Crimson King himself.
Magnus, filled with remorse, initially chose to accept the Emperor's decree and offered no resistance. However, Horus, tasked with relaying the message, altered the Emperor's mandate. The order for arrest and interrogation was twisted into a decree of annihilation.
This treachery led the Wolf King to launch a full-scale assault on Prospero. Magnus, unaware of the change in orders, had even dispersed his fleet and commanded his sons not to fight. Only when the sky darkened with orbital fire did he realize the horror of the situation. Despite the desperate resistance of the Thousand Sons, they were utterly broken by the combined force of Leman Russ, the Legio Custodes, and the Sisters of Silence. Prospero was razed.
In a crucible of despair, Magnus was once again seduced by the power of Tzeentch. He led his surviving sons into the embrace of Chaos, fueled by a tragic misunderstanding of the Emperor's intent. Due to the high concentration of psykers within the Legion, the Thousand Sons suffered horrific mutations. To save his brothers, Chief Librarian Ahzek Ahriman cast a potent spell. While the Rubric of Ahriman halted the mutations, it had an unintended consequence: the bodies of all but the most psychically gifted vanished, leaving only dust animated by sorcery within their power armor. They became beings suspended between life and death.
Lacking physical flesh, they became highly resilient to conventional weaponry. Bolters and plasma cannons often left mere scorch marks on their plate; they could only be truly extinguished by the total structural destruction of their armor. Eventually, the Imperium learned of this state. High-quality anti-psyker munitions, laced with the powdered remains of Sisters of Silence, proved exceptionally effective against these Thousand Sons warriors, who were now essentially akin to daemons of the Warp. Against such rounds, a Thousand Sons warrior was more fragile than even a World Eater.
…
Axion searched the workbench meticulously. While the psykers of the Hollow Mountain had spoken of a "journal," Axion knew that conventional paper could never have survived ten millennia of recording such vast quantities of data, nor could it support active research logs. The only logical conclusion was that this "diary" was an electronic device.
A journal capable of functioning for ten thousand years.
Axion pulled open a drawer beneath the workbench. Inside lay an object that resembled a codex but possessed distinct electronic characteristics. A scanning beam swept over it. No serial numbers or insignias were found.
However, its form was familiar to Axion.
"A Sonorg-United Manufacturing Second-Generation Book-Type Quantum Storage Device?"
This was a civilian device from the era of the Old Federation, part of the second wave of consumer electronics to adopt quantum storage modules. It had once been marketed across the Federation with the selling point of infinite storage capacity, a traditional book-like aesthetic, and support for archaic manual script input. Many Creators, known as "Collectors," had purchased this model to experience the "ancient joy of writing."
As quantum storage technology advanced and sapient machines evolved, these rudimentary storage devices, which lacked even basic artificial intelligence, rapidly lost their commercial viability. It was evident that the casing of this specific data recorder had been replaced; it lacked the identification codes the Federation had legally required to be displayed prominently.
Axion, however, found this unsurprising. These ancient devices were simple in structure and remarkably easy to maintain. Internally, they consisted of little more than a micro-recorder module equipped with a quantum storage chip and a somewhat more complex generator for projecting virtual, physical "pages."