The lower deck of the Gemstone is rotting.
The Rust Plague seemed to have a life of its own, spreading silently along the welds and pipe joints of the bulkhead.
The optical lenses of the monitoring array were completely clouded, and the signals from the Servo-skull became intermittent under the corrosive influence of the plague, eventually fading into silence.
The electronic systems that were originally used to monitor every corridor and every hatch were extinguished one by one by the Warp plague, and the lower levels were completely plunged into unseen darkness.
But the spread of the plague stopped at the dividing line on the middle deck.
That's where the ship's core compartments are located.
The reactor's secondary control station, the main thruster's energy distribution center, the stasis chamber for the Astropath, the Ecclesiarchy's accompanying chapel...
From the day the ship was built, these compartments have been subjected to daily applications of holy oil and inscriptions of prayers by the Adeptus Mechanicus technicians.
The blessings of the Ministorum Priest are like layers of glaze sealed onto the armor plate.
More importantly, these core areas are easier for the Machine Spirit to control.
It has witnessed the tearing of Warp Storm and the explosion of void torpedoes during its thousands of years of navigation.
Through countless attempts at being eroded by Chaos, the Machine Spirit itself possesses an almost instinctive resistance to Warp.
The Rust Plague has struck an invisible wall.
The rampant rust surged and hissed at the dividing line, like waves crashing against a breakwater, yet it could only advance slowly forward.
The bottom layer is a murky yellowish-green, while the middle layer is a cold metallic gray, with the two colors drawing a clear boundary on the deck.
Major General Dominic stood in front of the holographic projection on the command platform, his eyes fixed on the dividing line.
He cracked his knuckles, a habitual gesture he made when he made up his mind.
"Move all mobile forces to areas with good mid-level surveillance." His voice was unwavering.
"Abandon blind spots in surveillance at the grassroots level and avoid unnecessary searches."
"Deploy all heavy firepower points along the demarcation line, guarding only those areas untouched by the plague and within sight, denying them the opportunity to operate in the dark."
The order was relayed swiftly.
The garrison troops, originally scattered across the various levels, began to converge towards the middle level. The 30,000-strong naval garrison was deployed layer by layer along the main passage, and the engineering corps urgently erected temporary blast walls and heavy weapon positions at key nodes.
Since we can't see the enemy in the darkness, let's retreat into the light and force them to come out of the shadows for a face-to-face confrontation under surveillance.
This is the best solution Dominic could think of.
On the other side of the dividing line, Phelps also noticed this.
The Death Guard warrior stood in a completely corrupted maintenance passageway at the bottom level.
Underfoot was a thick, pus-like layer of corrosive liquid, and above, pipes dripped a foul-smelling liquid.
It slammed into his Power Armour shoulder plate, which was covered in rotting flesh, with a dull thud.
His perception had long surpassed that of ordinary people; the plague itself was his eyes. He could "see" the boundaries of the plague's advance.
They could "sense" the heavy, almost solidified power of faith and the will of the Machine Spirit in the area ahead.
The progress is stuck.
Moreover, he also sensed the deployment of the middle layer of defense.
Almost all of them were ordinary naval soldiers, with complete organization and dense formation. At each node of the defensive line, there was the aura of faith of the Ministorum Priest.
Those golden, warm spots of light, like red-hot branding irons, kept the plague at bay.
Under the priest's blessing, the soldiers formed human walls, their morale high and their formation stable.
This was a setup specifically designed to counter his preferred tactics.
Phelps curled into a disdainful smile, his rotting lips revealing several disgusting cracks.
Feint attacks, infiltration, night raids, using darkness to divide and surround... these were indeed his favorite methods in the past.
To defeat the many with the few, to tear apart the defenses of mortals with the tricks of Chaos, and to slowly toy with the prey like a cat playing with a mouse.
But that's not all he can do.
Things are different now.
He raised his head, and a murky green light shone through the slits of his decaying helmet.
The narrow passageways of a ship are the best weapon in themselves; no matter how many people there are, they can't spread out properly in such narrow corridors.
Of the 30,000 defending troops, only a few thousand could simultaneously engage in frontal fire support.
Now, he possesses plague vehicles, an organized army of zombies, and endless plague bestowed upon him by his Grandfather Nurgle.
Intrigue and schemes? No need.
Just run them over head-on.
"Get up," Phelps said softly, his voice as quiet as the rusting of a machine grinding in the background.
His will spread along the network of the plague.
Just recently, tens of thousands of naval soldiers, slaughtered by him and his men, are now lying dead in the cabins and passageways of the lower levels.
The Rust Plague had seeped into every inch of their bodies, corrupting their bones and muscles, and transforming their corpses into zombies subservient to the plague.
More than eight thousand corpses stood up simultaneously.
It was a horrifying sight.
The broken bones snapped back together, the everted internal organs were pulled back into the abdominal cavity by the rotting fascia, and a murky yellowish-green light shone from the empty eye sockets.
They stood up unsteadily, still clutching the Lasgun and bayonets they had used in life, their movements stiff yet carrying a stubborn sense of direction.
They then all headed towards the middle defensive line.
At the same time, the dozens of vehicles infected by the Rust Plague also completed their transformation.
Rust had covered their metal casings, and the hydraulic lines no longer flowed with engine oil but with thick pus.
The robotic arm twisted into a bizarre claw shape, and when the engine started, it emitted not exhaust fumes but a yellowish-green plague-like smoke.
They emitted a low, hoarse, mechanical roar, like a giant beast suffering from tuberculosis.
Eight thousand zombies and dozens of plague vehicles formed an army exuding an aura of death and decay.
On their opposite side was the first line of defense meticulously laid out by the Gemstone.
Thirty thousand garrison navy, heavy weapons positions, blast walls, and reconnaissance mines scattered around the defensive line.
The landmines were quietly placed by the engineers in the maintenance pipes, ventilation shafts, and equipment compartments around the defense line, covering almost every possible blind spot.
Each landmine is equipped with the most sensitive vibration and sound sensors, which will detect any object approaching the trigger range.
It will detonate within 0.1 nanoseconds, emitting a piercing, directional sonic shockwave that can both warn of an attack and cause damage.
This is an impenetrable security network.
Phelps knew the other party was on guard.
His senses about the plague told him that the metal interlayers around the defense line were filled with countless tiny gadgets, each bearing the characteristics of a dangerous explosive.
But he didn't care.
"Go ahead."