As the Executor Heavy Tanks ground into position, Axion blinked across the battlefield in a blur of displacement, reappearing in the center of the armored formation. No longer burdened by the immediate directive to shield his master, the Aegis Protector was fully unleashed. Even the veterans of the Inner Circle appeared fragile before the combat sub-routines of a multi-augmented machine of the Dark Age.
Though their transhuman reactions saved the Dark Angels from being instantly bifurcated by the Protector's twin molecular-vibration blades, the knights of the First Legion found it impossible to mount a meaningful counter-offensive once the machine closed the distance.
Its humanoid frame afforded it peerless agility, while its data-banks, laden with combat archetypes from a forgotten era, granted it a martial prowess that eclipsed even the Sword Brethren of the Black Templars. The massive machine moved with ghostly fluidity amidst the clashing steel, every sweep of its blades sending Dark Angels reeling, their own swords shattered or parried with bone-breaking force.
Bolter fire sparked harmlessly against the Protector's heavy-duty energy shields. Two Dark Angels who attempted to flank the construct were a fraction of a second too slow; they were instantly hewn in two.
Seeing his progeny slaughtered, Lion El'Jonson let out a guttural roar. He raised the Emperor's Shield, intercepting a lethal overhead strike from the Aegis Protector, and kicked a nearby son out of the path of a follow-up blow. In a fluid motion, the Lion drew his blade, striking for the machine's ankle actuators.
The Aegis Protector was humanoid, but it was not human.
Its arm joints inverted with a sickening mechanical whine. The direction of its blade shifted from an upward parry to a downward sweep in an instant, effortlessly knocking the Lion's sword aside. Before the Primarch could recover, the machine drove a heavy metallic foot into the center of the Emperor's Shield. The colossal force of the kick sent the Lion flying backward.
Belial, Ezekiel, Asmodai, and Azrael struck simultaneously.
Ezekiel brandished his force staff, weaving a web of psychic energy to arrest the Lion's fall and stabilize him. Asmodai swept his blade in a low arc toward the machine's midsection, while Belial and Azrael lunged from the rear.
"Enough! Cease this at once!"
Guilliman's voice thundered over the din of battle.
None of them listened, not the Inner Circle, and certainly not the Lion.
Seeing his brother preparing to lunge back into the fray, Guilliman acted on instinct. He stepped forward and deliberately tripped the Lion.
The Lion spun around, his face a mask of incandescent fury as he glared at Guilliman.
"Guilliman, you err gravely this day! All I do is for the future of the Imperium, for the mission our Father entrusted to us. You cling to a false stability, blind to the greater perils lurking in the shadows! The Dark Angels have never harbored treachery; I fight to excise the rot that threatens our foundations. Step aside, or you shall be remembered as the obstacle that broke the Imperium's path to glory!"
Guilliman did not retreat before the Lion's wrath. Instead, he simply pointed a single finger toward the perimeter.
The Lion followed the gesture, his pupils constricting in an instant.
Seven Executor Heavy Tanks had leveled their massive muzzles directly at the center of the plaza. Axion stood among them, cold and indifferent. Flanking the tanks were two Peltast Sniper Automata, their long-barreled rail-cannons hummed with charging power. Behind them, the Automated Sentry-Troopers had formed a perfect firing line, their power swords shimmering with arc-energy and their black emitters locked onto every Dark Angel in sight.
Still locked in melee, the Aegis Protector parried a flurry of blows while its vocal emitters activated.
"Adhering to Collaboration Protocol. Collaborator Guilliman: per the established articles, to ensure your safety, please evacuate your personnel from the current combat zone immediately."
The battle preparations were complete. As a Man of Iron, Axion felt no hesitation about sacrificing the Aegis Protector in a crossfire once the target area was saturated. He had delayed only because his units were still deploying and Guilliman remained within the "danger close" radius.
If he fired blindly, it would cause a total collapse of the Collaboration Protocol. Until Axion had secured sufficient self-preservation assets, he had no desire to trigger an irrevocable conflict with the administrator of the current Imperial era.
Guilliman had long suspected the Iron Man's cold methodology, but he asked the question anyway, his voice tinged with disbelief.
"And if I leave? What happens here?"
The Aegis Protector did not withhold the answer. It pivoted slightly, catching a strike from Azrael and effortlessly flipping the Supreme Grand Master through the air. Azrael slammed into Ezekiel just as the Librarian was channeling a psychic bolt. In the same motion, the machine's heavy lasers fired, forcing Asmodai and Belial to dive for cover.
The two masters were hurled into a nearby structure by the concussive force, vanishing into a plume of stone dust.
"All Dark Angels in the designated zone are currently target-locked. Upon area saturation, Extermination Protocol will be initiated. This unit shall be reconstructed following the engagement."
Guilliman could not abandon his brother, yet he dared not let the situation escalate into a war of annihilation.
"Lion!"
Guilliman stared at his brother, pointing toward the besieged Dark Angels.
"Not even our Father would tolerate such stupidity! You would turn upon an ally for the sake of your ridiculous secrets? Do you wish to see the tragedies of our past repeated?!"
The Lion stood up, his hand gripping Guilliman's shoulder with bruising strength.
"This is the honor of the First Legion, and its burden! The Dark Angels are the Emperor's most loyal warriors. Everything we are—"
CRACK-CRACK!
Two sharp reports echoed across the plaza. Hyper-velocity sniper shells streaked toward the dust clouds where Asmodai and Belial were attempting to regroup.
From the center of the tank line, Axion was orchestrating the slaughter.
In a momentary gap in the Aegis Protector's positioning, Axion had fired. The two heavy rounds whistled through the air, sealing off any path of escape for the two Inner Circle masters. If those shells hit, neither would survive.
The Lion shoved Guilliman aside and hurled the Emperor's Shield with a desperate, superhuman throw.
The first shell detonated against the shield in a blinding explosion. The shockwave knocked the second shell off its trajectory; it hummed past Belial's chest-plate, missing him by a hair's breadth, before striking a masonry building behind him. The structure vanished in a gout of pulverized stone.
The sheer destructive yield was staggering.
Axion adjusted his optical focus, locking his gaze onto the Lion.
"Revision: Threat level escalated. Guilliman, evacuate the strike zone immediately. The Iron Man can no longer guarantee your safety."
The Aegis Protector turned its glowing crimson eyes toward Guilliman.
The Lion's mind raced as the pieces finally clicked into place.
Collaborator.
Iron Man?!!!
"Those things are Men of Iron?!" The Lion's voice was a low, dangerous snarl. "Autonomous, sentient Iron Men?!"
"Guilliman! What have you done?! The danger of the Sapient Machine was so great our Father personally expunged one of our brothers and erased his Legion from memory for less!"
Facing the Lion's condemnation, Guilliman's expression was one of genuine bewilderment.
The Lion turned away in fury, but Guilliman began to sift through his own memories. They felt... fragmented.
He struggled to recall how it had happened. When he first found Axion, he was but a single mechanical entity. Then, suddenly, there was an Aegis Protector. After a visit to Cawl, there was a squad of Armored Wardens. He had hoped to use the Necrons to whittle down Axion's strength, yet every time the machine left his sight, it returned with a literal army of Iron Men.