As the long construction cycle hummed in the background, Axion began accepting a continuous stream of missions from Leontus directed at the Tyranids. Four Swarm Strikers and a transport laden with troops became a frequent sight across the Segmentum's war zones.
The fleet translated out of Mandeville points across the sector. In every system, the assault cruisers would accelerate, delivering point-blank strikes at hyper-velocity. Thick neutron beams charred bio-ship carapaces, while neural-shredder cannons sent the xenos vessels into lethal convulsions. The daggers of the fleet literally dismembered bio-ships by ramming through them, while drones and particle streams erased the smaller organisms.
Once the void was purged, the transport would deploy its cargo pods. Legions of Automated Sentry-Troopers swept through the ground swarms, their fire-patterns turning xenos waves into mulch. Synapse creatures were torn apart by the claws of the Destroyer-class Heavy Automata. Every pulse of the energy shockwave weapons cleared entire sectors of the battlefield.
With such absolute orbital superiority, the Iron Man ground forces were unstoppable. They moved in a relentless, non-stop advance. High-energy particle beams that could core a bio-ship were used to perform "surgical" deletions of Tyranid Bio-Titans.
Within days, the Imperium would receive a "clean" planet, marred only by slight residual radiation and mountains of xenos corpses. The tide of the counter-offensive was rising.
For the Hive Mind, it was a catastrophe. The Iron Men's kill-rate was so high it began to outpace the swarm's ability to spawn replacements.
Axion, however, was hunting more than just glory. He was searching for more Leviathan tendrils. In recent battles, he had found several fallen worlds and "roasted" the xenos remains, but while standard bio-ships contained metals, they lacked the rare IUF-93291 alloy. It was clear that this extra-galactic material was exclusive to the macro-appendages.
To reinforce his entire legion's weaponry, he needed to find those tendrils, shatter them, and reclaim the "ore."
Over several weeks, Axion reclaimed twenty-one planets and six star systems. To the soldiers of the Astra Militarum, the efficiency of these machines was soul-crushing. A single automaton possessed higher combat efficacy than a Space Marine. They required no logistics in the traditional sense, gave no conflicting orders, never rested, and ignored casualties. They were the personification of cold, lethal logic.
The Guardsmen, who had always been told they were the "Hammer of the Emperor" and the "Foundations of Victory," suddenly felt obsolete. The "Grip of the Enemy" seemed fragile beneath the tread of these metal gods. Regiments like the Cadians and the Mordian Iron Guard felt a profound psychological blow. Even the Astartes felt the shadow. Their legends of blood and sacrifice seemed small next to the mechanical slaughter.
Ancient Dreadnoughts, awakened for war, watched the Iron Men and felt a haunting sense of déjà vu. They remembered the Great Crusade, when Legions, not Chapters, fought by the hundreds of thousands under the Primarchs. Back then, the enemies of the Emperor were swept away with the same merciless, crushing weight. The battlefield looked like a memory made manifest: the tread of iron over the broken remains of resistance.
This shift in morale did not go unnoticed. The Ecclesiarchy and the Departmento Munitorum issued urgent pleas to the Theater Command, demanding the Lord Solar cease this method of warfare. The efficiency of these killing machines was poisoning the spirit of the Imperial troops.
Commanders of battered regiments began to ask why these machines hadn't been sent first, sparing their men such sacrifice. High-ranking Generals questioned Leontus's intent.
Leontus, following the principle that a good tool should be used until it breaks, decided to send Axion's forces deeper into occupied space. Their role shifted from frontline support to independent planetary and systemic purgation.
Axion did not care; he only cared for the mission.
However, a new problem arose. The occupied zone was like a pool of oil-slicked water. Every time Axion's fleet entered a system, like a drop of detergent, the oil scattered.
Whenever the silver fleet arrived, the Tyranids would immediately accelerate their biomass reclamation, leaving behind worlds scoured to the bedrock before fleeing into the void. Biomass that couldn't be retrieved in time was simply abandoned.
Axion watched his kill-counts stagnate as the xenos refused to engage. Finding only capillary towers and empty reclamation pools, he would land his Destroyers to "roast" the planet anyway, hoping to refine whatever metallic traces remained in the bio-sludge.
When the following Imperial forces arrived, they found planets that looked as though they had been struck by an Inquisitorial Exterminatus—seared beyond recognition. Yet, the infrastructure and machinery were often intact. The swarm only cared for meat, and the Iron Men had no use for Imperial hab-blocks. The reclamation pools were incinerated into glass pits.
Occasionally, an Imperial administrator would notice that rare ores or industrial equipment, items the Tyranids usually ignored, had vanished from the Hives. But compared to the value of a liberated world, the loss of a few high-end machines was a trifle. No one dared to ask where the "payment" for the Iron Men's services was going.