"ROAR!"
Inside the Webway, the daemons bellowed with a feverish, predatory excitement as they surged forward. Within the gloom of the distorted sub-dimension, a suffocating carpet of Neverborn crushed against one another, a tide of Warp-spawned filth driving toward the breach.
BOOM!
Against such densely packed foes, the modified Destroyer-class Heavy Automata deployed the simplest of solutions.
Incandescent promethium fire bathed the entire sector.
The daemons charged as if throwing themselves into a planetary crematorium. In an unending stream, they were reduced to drifting ash, their essences scoured from reality. Those behind them struggled frantically to retreat, only to be forcibly shoved into the inferno by the sheer momentum of the thousands pressing from the rear.
The throng was a chaotic gestalt of the Warp: shrieking heralds of the four Ruinous Powers intermingled with "wild" Warp-beasts and twisted, unaligned monstrosities. Their disparate warp-fire and malevolent energy strikes, however, achieved nothing against the extreme thermal output of the machines.
The plagues of Nurgle found no purchase on cold steel; the blood-greed of Khorne's scions and the sensory subversions of Slaanesh met only the silent, unresponsive logic of the machine. The Destroyers simply held their ground, gout after gout of flame erupting from their heavy projectors, incinerating the unnatural horde like dry chaff. Even the kaleidoscopic energy bolts of Tzeentchian horrors failed to breach the heavy, shimmering aegis of the automatons' void shields.
Once the vanguard of Destroyers had stabilized the immediate kill zone, more heavy units were funneled in. These units had not undergone chassis modification; instead, they were laid horizontally and shoved through the gate by the brute force of Armored Wardens.
For every Destroyer that entered the Webway, ten Armored Wardens followed in its wake. Upon crossing the threshold, the heavy units righted themselves, igniting their projectors to push the wall of fire deeper into the labyrinthine depths of the Webway's branching nodes.
Aside from the crackling roar of high-temperature plasma and the wet, tearing sound of massive power claws rending ethereal flesh, the Webway was filled only with the agonized wailing of the damned.
Compared to the desperate battle cries of Imperial troops or the deafening thunder of bolt shells, the advance of the Sapient Machine legions was chillingly silent. It was a cold, efficient slaughter, an industrialized purge occurring within the veins of the universe.
Phalanxes of Automated Sentry-Troopers marched through the gate in perfect, rhythmic lockstep, forming rigid mechanical squares to follow the advancing Destroyers and Armored Wardens.
The sheer scale of the daemonic infestation, which would have exhausted even a phalanx of the Legio Custodes, posed no such logistical complication for the machines. Until metal fatigue set in or energy reserves were spent, the mechanical tide would not falter.
To ensure the Emperor's laboratory was found, Axion did not merely commit the mechanical legions of the Titan's Spear; he activated a backup shell of himself and dispatched it into the fray. Should the Webway gate fail or communication be severed, this proxy would assume local command of all forces to ensure the mission's completion. Along with him, the meticulously preserved "Key" to the laboratory was sent into the dark.
Axion did not know the functional range of the Key's resonance. But he knew one thing: once the Webway was purged of the daemonic filth choking it, the path would be clear.
The daemons were both an obstacle and a compass. In the directionless void of the Webway, one could not get lost if they simply followed the scent of the enemy. Data analysis suggested that the daemons likely filled every transit vein within the vicinity of the Sol System. If a tunnel was found empty of the Neverborn, it was almost certainly a dead end or the wrong path.
Navigation, a nightmare for mortals, was a matter of cold geometry for the Iron Man. At every junction, a small squad of Sentry-Troopers established a temporary waypoint, serving as a communication relay and an energy recharge station. The quantum power transmission network functioned perfectly within the Webway's unique physics.
While other beings might starve or lose their minds, the Iron Men required no sustenance. The energy lattice ensured the cost of logistics was virtually zero. Any damaged chassis were repaired on the spot by swarms of nanites.
Over the course of half a month, Axion funneled nearly several hundred million mechanical units from the Titan's Spear through the gate. Yet, according to the emerging cartography, the Webway's structure was as complex as an infinite ant colony. The intersecting tunnels were countless. These hundreds of millions of troops had managed to explore barely half of the Webway spans within the Sol System's reach.
The vanguard outposts had thinned from squads of twelve Sentry-Troopers to single sentinels, or in some cases, a pair of Heavy Automated Defense Turrets left to hold the line. As for the daemon kill count, Axion had long since stopped recording it. The numbers were beyond meaningful calculation.
The Key had passed through a fifth of the cleared sectors, yet no resonance had been detected. But Axion was patient.
Logistical reinforcements from Segmentum Pacificus had just arrived.
Beyond the hundreds of millions of fresh mechanical troops carried by forty transport ships, five hundred Guardian-class multi-role vessels had arrived. The sight of such a massive fleet nearly caused the Imperial Navy commanders to suffer collective heart failure.
Only through the "intervention" of the Custodes and Roboute Guilliman did the Lord Solar and the High Admiral finally regain their composure.
As for the Inquisition, they had been desperate to refuse Guilliman's proposal. But the Primarch had offered only one sentence in response:
"A refusal may cause the Iron Man's fleet to vaporize the whole of Terra in an instant. Should that happen, you shall be the ultimate traitors to the Imperium."
Guilliman knew that Axion recognized the Emperor's status as a human, and that the ancient construct had vowed never to kill a "Creator." So long as the Emperor's life-sign persisted upon the Golden Throne, the Iron Man would not destroy the throneworld or the Sol System.
The Inquisition, however, knew nothing of this pact.
Terrified, they immediately reversed their stance and accepted Guilliman's edict. The modern Imperium was much like the shield in an Astartes' hand, one side bore the bones of a Sister of Silence, the other the skeletal form of the Emperor himself.
Upon reflection, escorting the Black Ships and ensuring the collection of the tithe was not an entirely unwelcome prospect. The Black Ships were always prime targets for rebels, heretic warbands, and void-pirates. While the Inquisition's Stormtroopers and Astartes reinforcements usually prevailed, the skirmishes inevitably delayed the tithes. With the instability of the Warp, additional protection was a boon.
After all, the Imperium lacked the manpower to properly shield the Black Ships. The tithe collection usually relied solely on the ship's internal security and whatever "canned" warriors were available.
The Inquisition contacted the League of Black Ships, allotting the first five hundred escort slots to their disposal. The League had no power to refuse; they set to work immediately. For the first time, many Black Ships heading into the dark, remote corners of the galaxy found themselves under the shadow of a guardian.
For the captains of the Black Ships, it was a surreal experience.
As the Guardian-class vessels followed their new directives to rendezvous with the Inquisitorial fleets, the galaxy was poised to be ignited once more. But unlike the fires of the Horus Heresy that burned the Imperium, this time, it was the traitors and the xenos who would be put to the torch.