As the Astra Militarum commenced their planetary landfall and deployment, they consulted the original charts of Ornsworld in an attempt to locate its most ancient bastion-capital, the Fortress of Hoopstanler. However, aerial reconnaissance from Thunderhawk gunships revealed a landscape utterly transfigured. Amidst the geographical ruin, a single feature stood in defiant prominence: a towering spire of black stone.
Atop the spire hung a massive green bell, its presence radiating a sickening, perverted sense of the sacred.
"Destroy that object," came the vox-command the moment the Thunderhawk pilots relayed their report. With detached precision, a pilot depressed the weapon release.
In that heartbeat, a bolt of emerald lightning arced upward from below. It struck the Thunderhawk with absolute fury, slagging half the fuselage in an instant. Deprived of any chance for evasive maneuvers, the gunship plummeted toward the earth in a death spiral.
Twenty regiments of the Astra Militarum stared out at a world devoid of life. The air hung heavy with a foul stench, though it lacked the distinctive, cloying rot of Nurgle's corruption. Instead, the landscape was a churning expanse of heaving earth and treacherous quagmires.
"The Thunderhawk is down; there is no doubt the traitors have entrenched themselves here. They must be purged at any cost," the Astra Militarum Commander declared, slamming his fist onto the tactical hololith as the vox-channel from the gunship dissolved into static.
In short order, the Imperial tithe-regiments established a perimeter on a rare patch of stable ground, erecting hasty fortifications. Yet, this conflict already felt alien to them; it was not the thunderous, grand-scale warfare they were accustomed to, but a war of deathly, suffocating silence.
"These Ratling traitors excel at sniping and reconnaissance. I had hoped they would be foolish enough to cast themselves against the Hammer of the Emperor, but they are not so reckless," the Commander mused, forcing himself to remain calm.
The Hammer Strikers Space Marines had already reported the loss of five battle-brothers in the opening minutes. The survivors had only endured by retreating into the armored hulls of Rhino transports and hermetically sealed bunkers. With the terrain so punishingly complex and no visible targets to engage, the prospect of suppressing this rebellion seemed increasingly grim.
"Was the Thunderhawk not downed near that spire?" one Colonel interjected. "That site is clearly of strategic significance. If we mass our strength and strike there, we will find our enemy, or, at the very least, when the decision is made to enact Exterminatus, we will not be accused of idleness."
"Agreed. We proceed," the Commander nodded. He immediately ordered the Leman Russ battle tanks and Sentinel walkers to provide flank security. Twenty regiments coalesced into a single, massive spearhead, driving directly toward the ruins of Hoopstanler.
His logic was simple: level the site, slaughter the traitors, and satisfy the record-keepers. As for the Inquisition, they could sift through the ashes to their hearts' content once the sector was secured.
Under the barked orders of their officers, the Imperial host began its grueling advance.
Hidden within the jagged terrain, Ratling snipers, clad in camouflaging Rat-mesh cloaks and wielding rifles fitted with Warp-scopes, crouched in wait. These abhumans, always naturally gifted marksmen, had now fully embraced the skaven-like treachery of their new masters, peering through their lenses with predatory patience.
As the column entered a narrow valley, the surrounding clusters of giant green crystals emitted a violent magnetic field. The interference was so potent that even the Astartes' auspex arrays flickered and failed. Nevertheless, the sight of the Imperial host, an endless tide of steel and man, offered a lingering sense of security.
Then came the muffled cracks of high-velocity discharge.
The heads of dozens of Guardsmen vanished in sprays of gore; the kinetic force of the impacts flung their bodies backward into their comrades.
"Contact! Sniper fire!"
Panic rippled through the ranks. Soldiers dove for the dirt or scrambled for cover behind track-links, their lasguns spitting wild, undirected fire into the crags. They fumbled for auspex reads, only to find themselves blind, the devices rendered useless by the Warp-tainted interference.
"Yes-yes..."
Having tasted first blood, a Ratling sniper hissed a low, gleeful chitter, his lips peeling back in a jagged grin as he reset his aim through the warp-lens.
The blind retaliation of the Imperial troops achieved nothing. Their only recourse was to quicken their pace, desperate to clear the valley. But as they pushed forward, the frequency of the fire intensified. At first, they left a few bodies every hundred meters; soon, the corpses were so thick that the Leman Russ crews felt the rhythmic vibration of bone and flak-armor beneath their treads like grim speed bumps.
Rank-and-file soldiers began brawling with one another, desperate to huddle within the shadows of the armored vehicles. This frantic scramble for cover choked the advance, grinding the Imperial momentum to a halt.
The Commander was incensed. Hamstrung by the rigid, archaic doctrines of the Departmento Munitorum, his force lacked the specialized mobility required for such terrain. They possessed the raw frontal power of the Leman Russ, but lacked the agility to flush out hidden harriers. The tanks could not hunt what they could not see, and the shattered roadways ahead required manual clearing by infantry who were being picked off one by one.
"Enough. These curs must be flushed out. Petition the Adeptus Astartes to purge these shadows," the Commander finally conceded. He requested two companies of Space Marines to deploy via Land Speeders and jump packs to clear the valley walls.
The Hammer Strikers, still stinging from the loss of five brothers, understood the risks. But for the Emperor's glory, there was no other path. A dozen Land Speeders roared into the air, carrying Astartes equipped for low-altitude vertical assault toward the valley's flanks.
"I despise this manner of shadow-war, brother," one Astartes grumbled to the Fourth Company's Lieutenant as their Speeder banked sharply. "There is no honor here. Our power swords were forged to slay lions, not to hunt vermin in the dark."
"Whether lion or vermin, if it bares its fangs against the Imperium, it must be extinguished," the Lieutenant replied, his voice stern. "That is our duty; it is the sole reason the Emperor saw fit to create us. And do not be complacent. I can feel eyes upon us, reaching out from the gloom."
"Impossible, surely?" the younger Astartes remarked, glancing around the reinforced, enclosed cockpit.
He could not see what lay beyond the physical realm. Miles away, a Ratling sniper, his right eye replaced by a mechanical optic provided by the twisted genius of Chrot, peered not at the Speeder, but through the veil of the Immaterium. Through this techno-sorcerous glass, he possessed a gods-eye view of the battlefield, shifting his perspective through the Warp to find the perfect moment to strike.
"No, no… these dogs of the False Emperor... their kennels are too thick, too thick-heavy!" the sniper cursed, frustrated by the layers of ceramite protecting his quarry.
As the Land Speeders closed in and the Jump Pack infantry began their professional, high-speed insertion into the sniper nests, the Ratlings began to fall. Yet, for every nest cleared, another Astartes failed to complete his jump, spiraling into the abyss.
One particularly bold Ratling sniper decided to risk his soul for a crowning act of sabotage. He began to overcharge his Warp-accumulation engine, intending to fire a shot that defied the laws of causality, a bullet meant to murder the Machine Spirit of the Land Speeder itself.
"Oh… to kill a spirit-soul... thank the Great-Great Horned Rat... a feat of glory-magnificence!" The Ratling adjusted his heavy power-pack, which began to emit a terrifying, low-frequency thrum.
Praying to the Horned Rat, he allowed half of his physical form to slip into the Warp. Through Chrot's unspeakable technology, he located the roaring, defiant Machine Spirit of the lead Land Speeder within the aether.
"Haaa..." The sniper exhaled, his finger squeezing the trigger.
A round of pure, condensed warpstone vanished into the Immaterium. This crystalline shard of raw Chaos struck the Machine Spirit with absolute finality.
In the materium, the Land Speeder did not explode; it simply ceased to be a cohesive machine. Its reinforced ceramite plating, its engine blocks, and its grav-impellers fell apart like a child's toy. The Astartes within reacted with superhuman speed, but the sudden disintegration flung fifteen of them into the rocky crags. Even for a Space Marine, the kinetic force of such a fall was devastating.
"Ugh! By the Throne, what happened?!"
Faced with the roars of his wounded brothers, a Librarian, blood seeping from a shrapnel wound in his neck, looked on with dawning horror.
"The enemy... they are sniping the Machine Spirits," he gasped. "They watch us from another dimension. There is no cover from them. We must relay this to the command!"
When the fragmented report finally reached the Astra Militarum Commander, the vox-caster sputtered with static-choked phrases: "Warp... watching... Eyes... No cover—"
Through this cryptic warning, the Commander realized the Emperor's Angels were facing something far more sinister than mere Ratling deserters. Based on the Astartes' intelligence, he designated this unseen, inter-dimensional threat with a new name: The Eyes of the Warp.