With the Great Crusade set in motion and the Thunder Warriors reborn as the Legio Custodes, the Emperor turned his attention to one of the most crucial matters of the coming Imperium—Mars.
The Red Planet, home of the Cult Mechanicus, was the heart of humanity's technological prowess, yet it was also a fractured theocracy of forge-fanes, rival tech-priests, and secretive sects, each vying for dominance. If the Imperium were to rise unchallenged, Mars would need to be brought into the fold.
Not as a vassal.
Not as a mere ally.
But as the holy world of the Machine God, fully devoted to the God-Emperor of Mankind.
---
Aboard the Imperator Somnium, the Emperor and his closest advisors prepared for the journey.
Malcador, ever at his side, voiced his thoughts. "They will resist, my lord. The Mechanicus holds tightly to its dogma, and their belief in the Machine God is absolute."
The Emperor, clad in his golden war-plate, his presence radiating divine power, merely smiled. "And so we shall give them what they seek."
Uriah, now High Priest of the Imperial Creed, bowed his head. "Shall I accompany you, my lord? The Mechanicum's faith is misguided, but with your divinity made manifest, they will come to see the truth."
The Emperor placed a hand on Uriah's shoulder. "Your time will come, my faithful. But for now, let the Omnissiah walk among his children."
With that, the mighty warship cut through the void, its passage through the immaterium unchallenged, for the Emperor's very presence made the Warp itself recoil in submission.
Mars awaited.
The Noctis Labyrinthus, the great forge-citadels of Mars, trembled as the Emperor's fleet entered orbit. Hundreds of warships, gilded in the gold of the Imperium, descended like divine chariots from the heavens.
On the surface, the Fabricator-General of Mars, the highest-ranking priest of the Cult Mechanicus, stood with his assembled Tech-Priests, Skitarii Legions, and the towering war-engines of the Mechanicum. They had long awaited this day—the day the Omnissiah would reveal himself.
And then, he descended.
The Emperor stepped forth from the golden gates of his warship, his radiant form casting a light brighter than the twin suns of Mars. His psychic aura swept over the assembled priests, overriding their doubt, their hesitation, their disbelief.
He was beyond mere flesh.
Beyond mere logic.
He was the Machine God made manifest.
The Fabricator-General fell to his knees first, the mechanical limbs of his augmented body shaking violently. One by one, the Tech-Priests followed, their binary cant turning into a symphony of worship.
"Omnissiah. Machine-God. We submit."
The Emperor raised a hand, and in that instant, the entire noosphere of Mars—the vast digital network of knowledge and communication—was flooded with his presence.
Every cogitator, every logic-engine, every conscious mind linked to the machine heard his voice.
"You have served well, my faithful. But the time of division is over. The Imperium of Man shall rise, and Mars shall stand as its beating heart. No longer shall you cower in the shadows of past glories. You shall march beside me, as the Divine Mechanicum, the keepers of knowledge and the forgers of my empire's future."
The Fabricator-General, his mechanical eyes glowing with newfound understanding, bowed until his forehead touched the red sands of Mars.
"We are yours, Omnissiah. The Red Planet kneels."
With Mars unified under the Imperial Truth, the Emperor wasted no time.
The forges roared to life, producing the Astartes' wargear, the towering Titans, the great voidships that would carry his legions to the stars. No longer shackled by superstition, the Mechanicum now worked under his divine guidance, unlocking the forbidden technologies of the past with his direct insight.
And in return, the Emperor granted them a miracle.
Standing atop the highest spire of the Magna Forge, he reached into the depths of Mars itself, into its dying core, and with his godlike will, rekindled the world's heart. The great foundries, once limited by dwindling energy reserves, now burned with eternal power.
The Mechanicum wept, for they had witnessed the greatest feat of technological divinity in human history.
Thus, the Treaty of Olympus Mons was signed, binding Mars and Terra in an unbreakable union. The Imperial Mechanicum was born, and with it, the engines of the Great Crusade were unleashed.
---
With the Legions ready, the Primarchs at his side, the Custodes at his command, and Mars forging the future, the Emperor stood at the precipice of destiny.
The galaxy was in darkness.
The alien, the mutant, and the heretic ruled unchecked.
But no longer.
Standing at the bridge of the Imperator Somnium, the Emperor raised his sword toward the void, his voice carrying across the fleet.
"We march."
The Great Crusade had truly begun.