It was through a convergence of various factors that the project known as the Punisher was eventually realized, culminating in a Standard Template Construct (STC) Master Template for an autonomous bipedal weapon platform designated the Castigor-class. Beyond the Castigor-class, plans existed for an even larger variant known as the Castigoth-class; however, the Federation collapsed before the Master Template for the latter could be finalized.
Standing one hundred and sixty meters tall, the machine featured a humanoid, bipedal design with twin power-actuated limbs. Its entire chassis was encased in heavy composite plating, reinforced by double-layered Neutron Armour. Driven by four Quantum Cores and stabilized by multiple gravity-adjustment arrays, its weight approached forty-five thousand tons.
This was nearly twice the mass of an Emperor-class Titan.
Unlike the Emperor-class Titans of the Imperium, a hunched, lumbering mountains of metal that carried massive cathedrals upon their backs, the Punisher Titan was devoid of such grotesque protuberances. Its power-spine was thick and straight; its skeletal frame was symmetrical and elegant. In silhouette, it resembled nothing so much as a colossal Space Marine clad in power armour, sans helm and power pack.
The reason for its staggering weight was simple: the Punisher was equipped with numerous energy cores providing surging power, while its dense Neutron Armour was designed to withstand a sea of physical trauma. It featured a form-fitting shield system similar to that of the Destroyer-class Heavy Automaton, and possessed nearly double the volume of super-magnetic electronic muscle fibers compared to an Emperor-class Titan.
Though difficult to conceive for a machine of forty-five thousand tons, its primary design requirement was agility. The Punisher was built to match the flipping, leaping, and fluid evasion of Aeldari Titans. Only by mirroring the enemy's mobility could it dictate the terms of engagement.
If the machine-body was the vessel of the Iron Men, and the Wraithbone Titan was a vessel driven by an Aeldari soul, then the Iron Men saw no reason for their war-engines to suffer any deficit in performance compared to their xenos counterparts. This design philosophy resulted in a Punisher that stood nearly three times the height of the largest Aeldari Phantom Titan.
Mounted on the vambrace of its left mechanical hand was a massive Power Claw exceeding forty meters in length. The right hand remained unburdened by fixed weaponry; instead, the humanoid structure allowed for a colossal mounting bracket on its back to house an Ultra-Heavy Multi-Barrel Cannon. With a bore exceeding six meters, each shell weighed hundreds of tons. When necessary, the right hand could draw this weapon for long-range bombardment.
The streak of light that had shattered the Aeldari Titan mid-air moments ago had originated from a shell fired by this very cannon.
Furthermore, paired with the Punisher-class was a power sword known as the Radiant Sun. Measuring ninety meters in length, the blade erupted into a brilliant golden radiance upon activation, a weapon forged to augment the Punisher's close-quarters lethality. Beyond these primary systems, the chassis concealed a multitude of "smaller" weapons and autocannons for anti-aircraft defense and the systematic purging of infantry-scale units.
Though its armament appeared simple, its destructive potential was anything but. The Punisher's variable gravity systems allowed the war machine to utilize any part of its chassis as a kinetic weapon. The Neutron Armour ensured the frame remained inviolate during such impacts. To eliminate mechanical latency, the Punisher utilized distributed Quantum Signal Transmission Nodes, discarding traditional cable looms. The sheer scale of its frame provided terrifying angular acceleration; when its sixty-meter mechanical arms swung, the extremities reached velocities that defied logic.
…
Within the dark city of Commorragh, even those Titans that had slumbered for ten millennia since the ancient Aeldari Empire had never beheld such horrific engines of war. Witnessing the gargantuan Punishers, several Aeldari Titans attempted a coordinated ambush against these staggering constructs.
The results were instantaneous and absolute.
Volleys from Antimatter Cannons proved meaningless; energy ripples shimmered across the Punisher's plating, creating beautiful but harmless undulations across the hull. A Revenant Titan, seeking a weakness, used its jump jets to strike at the Punisher's lower chassis. Before it could land a blow, the Punisher swatted it aside like an insect, the Revenant shattering upon impact.
A five-fold difference in scale dictated a slaughter, not a battle.
Compared to other mechanical constructs that might seem ponderous, the Punisher Titans tracked the Aeldari movements with predatory ease. It was as if an Astartes in Terminator Plate had waded into an army of mere mortals.
The lead Punisher drew its ninety-meter Radiant Sun power sword. Blinding golden light flared along the blade, the surrounding air emitting a terrifying hiss as the energy discharge ionized the atmosphere. A single, rapid horizontal cleave bifurcated the Aeldari Titans along with the spires behind them.
The other two Punishers gripped their Ultra-Heavy Multi-Barrel Cannons, systematically erasing the agile Revenant-class Titans. The Aeldari, who usually relied on their superior speed, found themselves facing a faster predator. Revenant and Phantom Titans were sliced into scrap by the golden blades, their remains ground into powder beneath massive mechanical feet. The Multi-Barrel Cannons reduced the Titans to red-hot mist; their psychic shields collapsed instantly under the weight of the massive shells.
The thunderous roar of the cannons echoed through the depths of Commorragh. The surrounding Drukhari host was flattened like wheat in a storm, tossed aside by the sheer atmospheric displacement of the shockwaves.
Panic finally seized the Dark City. The Drukhari shrieked in terror, fleeing blindly. Death began to metastasize throughout Commorragh.
The harvest of Dark Aeldari souls once again drew the gaze of Slaanesh. This time, however, She remained unmoved. Those "iron husks" had already humiliated Her in the Immaterium, nearly making Her the laughingstock of the Warp. She had no desire to intervene personally again.
Watching the ground war turn into a systematic culling, Slaanesh finally understood why Khorne found these entities so vexing. All the emotion on the battlefield emanated from the Drukhari; the machines possessed no concept of emotion to feast upon. Fear of death blanketed the xenos, and at this moment, Slaanesh, viewing the souls she consumed, had no desire to even savor their torment. She became a cold, mechanical devourer of souls, devoid of Her usual perverse fluctuations.
…
In stark contrast to the Drukhari's agony, another group within Commorragh received entirely different treatment.
Under the cover of the chaos, a band of several hundred Adeptus Astartes managed to breach their dungeon cells. These Space Marines hailed from various Legions and Chapters, having been imprisoned for vastly different spans of time. Among them were Ultramarines, Dark Angels, and Space Wolves, and even loyalist remnants of the Night Lords and Word Bearers.
These loyalists from traitor lineages had refused the will of their Primarchs and fled their Legions, wandering the galaxy to fight for the Imperium in their own way, only to be captured by Drukhari raiders through various misfortunes. Because they hid their identities and operated in isolation, they never expected rescue. They knew the Imperium would never launch an assault on the heart of the Dark City for a few hundred Astartes. Merely reaching Commorragh was a feat deemed impossible.
Yet today, the Emperor's Justice had descended.
These Astartes, who had been forced to fight as gladiators, had no memory or record of these "iron husks," but that did not lessen their hatred for the degenerate Drukhari. However, when these strange mechanical entities executed every other xenos species in the adjacent cells but bypassed the Astartes, and even wrenched open their gates, the loyal warriors were left in a state of stunned bewilderment.