"So… why exactly are we here?" one of the Scions muttered, his voice low but not low enough. "I heard from the Thetoid Gryphonnes that they encountered some unknown xenos down here, but that's not our mission, is it, Sergeant?"
"You do realize," the Tempestor replied without looking back, "that our Prime doesn't get to choose what mission we take, yes?"
The Scion swallowed. "Yes, sir."
"Then stay silent unless you have something vital to report."
The squad continued down the damp, reeking tunnels. Filth squelched under their boots, and the air tasted like rot and oil.
Many worlds across Camelarion had succeeded in containing the xenos infection—isolating outbreaks, sealing hab-blocks before they spread.
But some planets had failed.
"She promised we'd be hunting heretics and traitors," another Scion grumbled, kicking something soft and unpleasant that clung to his boot. "Not crawling after animals in this Emperor-forsaken sewer."
Other than Inquisitor Eisenhorn, Inquisitor Castil of Ordo Hereticus have also arrived with 46th Iotan Dragons and a large numbers of Inquisitorial Storm Troopers. Though, she arrived after the Camelarion Crusade have finished and, she's now working to make sure there's no Chaos cultist and traitors operating within Camelarion.
46th Iotan Dragons while also trained like the 43rd Iotan Dragons to fight in darkened environments and caves, renowned for their ability to "fight blind". This resulting 46th have been requisition by the Inquisitors of Ordo Hereticus and Ordo Malleus for many time to hunt the Chaos cults or traitors that dwell or hide in the darkness.
Now they moved through the mapped route a Thetoid Gryphonnes kill-team had cleared for them.
And at last, they reached it.
A junction—wide, dark, with pipes snaking across the ceiling like rusted veins—where one passage led further into the depths the xenos occupied.
"Spread out," the Tempestor ordered, stepping to the center of the junction. "Cover every corner. No one gets flanked."
His squad of eleven Scions moved instantly.
Three take the left route, two take the right route. While four formed a forward line covering the main tunnel that plunged deeper into darkness.
The last Scion, the auspex operator, crouched beside the Tempestor, adjusting the array with gloved fingers.
"Reading anything?" the Tempestor asked.
The auspex gave a soft, strangled beep.
"…Movement," he whispered.
The beeping quickened.
"…Multiple signatures. Fast. Very fast."
"Look like we have stir their nest." The Tempestor said as he take out his plasma pistol and activate the power sword. "Signal the Inquisitor, tell her we're successfully gain their attention."
"Yes, sir."
===
IC-78 - Lunar class cruiser
Orbit of Pollax
"The plan is progressing as expected, Mistress. The Deathwatch and the Storm Troopers stand ready for deployment," the acolyte reported as he approached.
Inquisitor Castil didn't even slow her pace. "Then why," she said sharply, "are you still standing here? Prepare the men and the Valkyries. I will lead the assault myself. And inform the Astartes they may prosecute the mission however they see fit—but the leader is to be taken alive. I want him for future study."
"Yes, Mistress," the psyker-acolyte answered quickly. He fell in step behind her, issuing orders through curt telepathic pulses that echoed softly in the corridor.
By the time they reached the hangar, its vast interior thrummed with activity. Ten Valkyries waited on their launch rails, engines whining at idle. Air crews gave final gestures, guiding squads of Storm Troopers as they performed last-minute checks on their gear. Hot-shot lasguns were slammed into power ports. Plasma coils glowed with controlled heat. Flamers were tested with restrained bursts. Even a few prized boltguns were clicked and locked.
Then came the Thunderhawk—hulking, armored, and unmistakably Astartes. Ten Space Marines stood before it, giants amid the bustle.
Three of them wearing Indomitus Terminator amour, one from the Imperial Fists, equip with a storm shield and thunder hammer, second one from Salamander, holding a heavy flamer, last one from Howling Griffons, equip with the same as the Imperial Fists.
Two close-combat specialists waited nearby.
A Black Templar, blade sheathed in flickering power, combi-flamer mag-locked to his side.
A Mortificator beside him, silent and skull-marked, axe and bolt pistol secured with ritual precision.
Another three are tactical marines. They come from Novamarines, Death Spectres and Raven Guard. Other than the Raven Guard who equip with a sniper rifle, the other two are equip with boltguns.
The last two are heavy weapons specialists. One from Iron Hands who equip with a plasma cannon, and the last from Ultramarine who equip with a heavy bolter.
The moment Castil entered, the Storm Troopers stiffened, hands tightening on their weapons. The Astartes filed silently into the Thunderhawk, leaving only the Imperial Fist outside—a silent sentinel, signaling his role as leader of the squad.
"Mount up," Castil commanded, her voice sharp and carrying across the hangar. "We strike now."
Engines roared to life. Vox-casters crackled with acknowledgment. Servitors released docking clamps with pneumatic hisses. The Valkyries and the Thunderhawk trembled as their weight shifted in preparation for launch.
Castil gave a brief nod to the Imperial Fist. He inclined his head in return, a gesture of confirmation.
With that, Castil stepped into the waiting Valkyrie, cloak fluttering behind her, while the Deathwatch Astartes secured themselves inside the Thunderhawk.
The hangar doors began to retract. Outside, the void of orbit awaited, cold, empty, and ready to deliver them into the xenos infested Hive world.
Other than them, there's already another group of Valkyries exited the cruiser from another hanger. In them, another group of Scions from 46th are being carry to the ground, assign to reinforce those on the ground or simply serve as the replacement of those that perish.
After all, their main mission is to divert the Xenos attention so that Castil and the Deathwatch can cut off the head. And if needed, the Scions will also push further into the darkness to provide help to them.
===
Screams echoed through the underground corridors, slipping through pipes and ventilation shafts. Some sounded close—far too close—but the Scions holding the junction knew the truth: the ones screaming were nowhere near them anymore.
Hot-shot volleys cracked through the tunnels, the whump of plasma fire followed by the roar of promethium flamers. None of it mattered to those entrenched in the junction. Only survival did.
"When are those reinforcements arriving!? We can't hold much longer!" a Scion shouted over the din.
The ground around them was carpeted with alien corpses—limbs sheared off by las-fire, bodies melted by plasma, others charred black by flame.
But not all the bodies were xenos.
Several Scions lay among them, or parts of them.
"Prime already said reinforcements are on the way!" another Scion yelled, firing both hot-shot laspistols in rapid bursts. "We can still hold!"
"Yes, we can hold the junction!" the Tempestor barked, cleaving a chittering head from its shoulders with a sweep of his power sword. "But those behind us can't wait any longer!"
Behind the firing line of six Scions, three more held position. Two of them were gravely wounded—one missing an arm entirely, the other impaled clean through the abdomen. A Scion acting as chiurgeon knelt over them, hands slick with blood as he worked frantically.
"Both of them are losing too much blood," the chiurgeon muttered, injecting another stabilizer. "The drugs aren't working… they're failing. Emperor knows why."
"Then keep trying!" the Tempestor roared. "When this is over, I'll make damn sure they buy you the most expensive drink on Camelarion!"
As he spoke, he fired another burst, the beam punching through a xenos skull and burning the thing from the inside out.
Then, through the chaos, a new sound rolled through the tunnels—deep, thunderous, unmistakable:
Valkyrie engines.
The roar vibrated through the stonework, the sound funneled down through one of the vertical shafts above the junction.
Cameleontine cities—even the manufactoria—were forbidden from allowing their citizens to live underground.
As a result, everything had to be built upward, stacked in towering layers of steel and ceramite. Over time, the cities had become vast artificial canyons, deeper and broader than those found on most Imperial worlds.
But such vertical sprawl left the lowermost districts in perpetual shadow. To prevent this, Atharion had commanded the Mechanicus to carve enormous open shafts through the cityscape—sunholes that ran from the surface all the way down to the deepest legally habitable strata.
Now, instead of sunlight, the shaft channeled the scream of approaching aircraft.
And to the Scions fighting for their lives, it was the sweetest sound in the galaxy.
"Reinforcements are here!" the Tempestor barked. "Move! Push toward the center!"
As they advanced, another noise joined the thunder of engines—
grav-chutes activating.
Seconds later, a full squad of Scions dropped straight down the shaft, firing their hot-shot carbines mid-descent. The opening was filled with red lances of light as they shredded the xenos clustered near the junction.
One of the new arrivals slammed boots-first onto a genestealer, crushing its skull as he deliberately cut his chute early.
"Emperor's bones—can't believe you're still alive," the Tempestor said, ripping his power sword free. "We lost contact with you hours ago. Thought you were dead."
"Well, you know me," the beleaguered Tempestor replied with a strained chuckle. Then he gestured to the two wounded Scions behind him. "But those two? Not sure. Stabilizers aren't slowing the bleeding anymore."
"The medicae will handle them," the newly arrived Tempestor said, already scanning the shadows. "Focus on what's ahead."
More Valkyries screamed overhead, depositing three more squads into the fray. With their numbers bolstered, the Scions began preparing a counter-push deeper into the infested undercity. They trusted their Inquisitor—whoever she sent into the dark would not be wasted.
But for now, they fortified their position and tended to their wounded.
---
Meanwhile, the Inquisitor's situation was far less forgiving.
A strike force of twenty Inquisitorial Storm Troopers advanced through a tunnel that spiraled toward the infestation's heart. In the front marched Inquisitor Castil, inferno pistol in one hand, power sword in the other, her bionic eye scrolling tactical feeds.
"How long until we link up with Group Secundus?" Castil asked, tone clipped. "We cannot waste any more time."
Without looking, she snapped her pistol toward a corner—and a trooper instantly fired his plasma gun past her shoulder, incinerating the genestealer lurking in the shadows.
"By my estimate," the Storm Trooper Sergeant replied, unnervingly calm, "we will rendezvous at the next junction. Groups Tertius and Quartus report heavy resistance and mounting casualties."
"I don't care," Castil said coldly as she fired her inferno pistol into the ceiling, burning a descending xenos to ash. "Either they reach their waypoint on time, or they will answer for their failure."
"Your will," the Sergeant replied without hesitation. "I will relay your order immediately."
The group pressed forward, boots splashing through pools of ichor as they moved deeper into the labyrinth. Minutes later, they reached the designated junction—only to find it carpeted with torn genestealer corpses.
But something was wrong.
"These wounds…" the Sergeant murmured, crouching beside a bisected body. "This isn't from any weapon we carry. And the beasts don't kill each other—not when they know prey is near."
Castil slowly surveyed the carnage. Limbs severed cleanly. Skulls crushed with impossible precision. Chitin split by blows too heavy for any human to deliver.
"Indeed," she said. "Which means only one thing—the Astartes have passed through here… or they still remain."
She finished her sentence just as a shadow peeled itself from the darkness beside her.
A Deathwatch Astartes of the Raven Guard stood at her left flank—silent, immobile, unseen until the moment he chose otherwise. None of her Storm Troopers had noticed his arrival. None even realized he had moved.
"We have located their leader," the Astartes said, his voice a low growl issuing from behind an emotionless black helm. "And the group meant to rendezvous with you here… is gone. Ambushed. No survivors."
"Where?" Castil asked, meeting the unblinking lenses of his helmet.
The Astartes gave no verbal response.
Instead, Castil's bionic eye flashed red—coordinates streaming directly into her optic feed.
She looked up again.
The Raven Guard was already gone.
One moment present, the next dissolved into shadow—leaving only the faintest shimmer of displaced air, and twenty Storm Troopers who had never realized he had been among them at all.
"Let's go," Castil snapped, already striding toward the far passage without waiting for acknowledgement. Her cloak swept behind her like a shadow dragged by purpose. "We waste no more time in this filth. Relay to all surviving Scions and Troopers—every unit still breathing is to converge on coordinate VD-657-D-8. That is where our quarry waits."
"Yes, my Lord!" the Sergeant barked, immediately opening vox-channels. "All teams, converge on VD-657-D-8. Move with haste—this is priority alpha!"
The junction came alive with motion. Storm Troopers fell into formation around Castil, weapons raised, scanning every pipe and shadowed alcove. The smell of plasma-burnt chitin still clung to the stale air.
Above them, the sun-shaft rumbled as more Valkyries circled for fire support. Below, the stone trembled with distant gunfire—somewhere, another unit was still dying.
Castil did not look back.
Her pace did not falter.
The inferno pistol in her fist glowed with residual heat, smoke curling from its barrel as though it hungered.