Qin Mo had overhauled the power armor.
The old battery system was the first thing to go. It had been serviceable when survival was the only requirement: enough charge to move, enough reserve to keep servos from locking mid-fight, enough output to feed basic weapons before the wearer became a decorated corpse. But serviceable was no longer acceptable. Not for the war spreading through the underhive. Not for the enemy adapting in the dark. Not for what Qin Mo intended his soldiers to become.
In its place, he built a new energy engine.
It was not a sacred relic dredged from some Mechanicus vault. It was not warp-based sorcery. It did not require xenos biomatter, unstable archeotech, or the sort of exotic voidship-grade components that would make a tech-priest reach for incense with one hand and a plasma pistol with the other.
It was a self-sustaining battlefield power source, designed to store immense amounts of energy and replenish itself while under fire.
The principle was simple. The battlefield wasted energy constantly. Lasfire bled heat into the air. Plasma discharges left residual ionization and thermal bloom. Explosions dumped pressure, light, and heat into the surrounding environment. Even enemy weapons that missed still paid their energy cost.
Qin Mo decided that waste was unacceptable.
The new engine drew from the battle itself. Lingering heat from lasgun volleys. Residual energy from plasma impacts. Thermal spikes from detonations. Electromagnetic noise from damaged machinery. Every discharge, every flare, every explosion became something the armor could capture, process, and return to use.
Everything was fuel.
The old energy plating was discarded as an independent system. It had worked, but it consumed too much power and treated incoming fire as a burden to endure. Qin Mo wanted incoming fire to become an asset.
In its place, he integrated a capture field directly into the grav-shield.
The new grav-shield had two primary functions.
Kinetic Neutralization — Bullets, shrapnel, and even tank rounds struck the field and lost coherence under their own momentum. Projectiles flattened, fragmented, or dropped as if the air around the wearer had become a crushing, invisible current.
Energy Absorption — Lasfire, plasma wash, and thermal radiation were drawn into the capture field, filtered through stabilizing circuits, and redirected into the armor's energy engine instead of bleeding uselessly into the environment.
The result changed the nature of protection.
Enemy fire no longer merely failed to kill the wearer. It strengthened him. The weapons changed as well.
The old rotary lascannons had been impressive in the crude way a shrine-world execution platform was impressive: loud, bright, heavy, and devastating when pointed in the right direction. But they were inefficient. They wasted too much energy in heat bloom, required too much cooling, and made precise fire difficult in confined spaces.
Qin Mo replaced them with multilasers.
Each weapon compressed multiple las-beams into a single high-density burst pattern, preserving the old weapon's rate of fire while increasing penetration and target stability. At close range, the effect was brutal. Armor plates split. Mutated flesh boiled. Barricades became glowing channels of slag before the enemy behind them realized cover had stopped existing.
For close combat, the battlefield had changed, and so had the tools needed to survive it. Every suit now carried a gravity hammer.
The weapon did not rely on weight alone. Its head was wrapped in a localized gravitational distortion field. A light strike could cave in armor. A full swing could turn bone, muscle, and ceramite into a pulped mass that barely remembered its original shape. Against mutants, armored cult champions, and anything foolish enough to close distance, it gave ordinary human strength the finality of a collapsing wall.
But even the hammer was secondary.
The true firepower rested in the shoulder cannon.
It was a modular weapon system built around adaptation rather than specialization. A single mounting. Multiple firing modes. No physical ammunition feed to jam. No crates of shells to drag through the underhive. No supply officer to tell a desperate squad that the right kind of round had been lost three tunnels back.
Mortar Mode — The cannon launched a superheated energy sphere that detonated roughly one hundred meters above the battlefield, scattering a controlled downpour of plasma fragments across enemy formations. It was not elegant. It was not subtle. It erased infantry concentrations and forced anything without overhead cover to die looking upward.
Heavy Cannon Mode — A long-range, high-velocity beam configured for armor columns, barricades, and fortified firing points. It punched through ferrocrete, vehicle plating, and layered scrap defenses with the patient contempt of a siege gun small enough to wear.
Gauss Accelerator Mode — A hypercharged kinetic slug wrapped in a stabilizing field, designed to tear through multiple bodies, light vehicles, and clustered targets in a single shot. It was the answer to narrow corridors, charging lines, and the underhive's habit of packing too many enemies into too little space.
Missile Launcher Mode — A guided energy projectile with onboard targeting logic, capable of adjusting its course through smoke, dust, and broken terrain. It tracked movement, heat, and mass signatures, ignoring decoys unless Qin Mo allowed the system to be fooled.
No conventional ammunition. No supply limit beyond power.
Only controlled, repeatable devastation.
And yet, Qin Mo was still unsatisfied.
The armor was powerful. The weapons were effective. The shield system worked. By any sane battlefield standard, he had already created equipment that could overturn local doctrine and make noble house bodyguards look like parade-ground ornaments.
But Qin Mo's standard was not sane. His vision was simple.
Power-armored warriors. Alone. Ending battles.
Not as infantry. Not as elite shock troops.
As demigods of war.
To achieve that, armor alone was not enough. A warrior could only dominate the battlefield if the entire battlefield was forced to support him. Mobility, reconnaissance, fire support, supply, extraction, command links, and repair capacity had to move with the squad.
So Qin Mo designed a new drone fleet.
....
These were not ordinary drones.
They were larger, smarter, and specialized for war in the underhive's broken vertical maze. Their frames were armored, their anti-grav systems overbuilt, and their machine logic limited enough to avoid independent stupidity while still being fast enough to matter in battle.
Energy Drones — Linked directly to the armor's energy engine, these units stabilized power flow, absorbed excess charge, and fed reserves back into the suit during extended combat. A warrior accompanied by one could fight far longer than any normal power source should allow.
Fire Support Drones — Heavy autonomous platforms fitted with lascannons, plasma projectors, rotary solid-shot weapons, and adjustable bombardment arrays. Their purpose was not to duel. Their purpose was to turn enemy concentrations into burning geometry on a tactical display before the armored troops reached them.
Transport Drones — Fast anti-grav carriers capable of dropping troops anywhere the underhive's architecture left enough space to descend. They cut through ash, smoke, and hot air, guided by onboard cogitators, auspex scanners, thermal mapping, and Qin Mo's own battlefield data-link.
The doctrine that emerged from those systems was straightforward.
Deploy only three power-armored warriors.
Send them by transport drone to sections of the battlefield where no Imperial allies were present.
Once the drop zone was clear of friendly forces, unleash the fire support drones. Let long-range bombardment saturate enemy formations, fortifications, artillery nests, and armor columns before close combat became necessary. Then the armored troops would land, advance, and finish whatever had survived.
Speed. Precision. Overwhelming dominance.
No slow trench crawl. No heroic bayonet charge into machine-gun fire. No praying that command had guessed correctly before ordering men into the dark.
This was Qin Mo's masterpiece.
The pinnacle of warfare he could produce with the resources at hand. But even this vision had a flaw.
The cost was astronomical.
Some components required tolerances no local workshop could achieve without Qin Mo personally reshaping the material. Some subsystems bordered on Necron-tier engineering in miniature. Certain parts could be fabricated only because Qin Mo was cheating on a level that would make every forge temple in the sector either declare him a saint, a heretek, or both within the same breath.
And Qin Mo had no intention of stopping.
After three days of design work, followed by four days of constructing AI-controlled logistics drones and three prototype armor sets, he decided the equipment needed a field test.
The opportunity came quickly.
A Call for Reinforcement
The 47th Regiment's eastern outpost received a transmission through a battered vox-relay that had already been repaired twice that day. Static filled half the message. Screams and weapons fire filled the rest.
Another Imperial force had made contact.
Their stronghold, ninety kilometers east, was under siege.
The enemy had broken through the outer defense line. Casualties were severe. Ammunition was low. The vox-operator on the other end did not ask for support with the formal restraint of an officer reading doctrine. He begged for it like a man watching the last door buckle.
They needed reinforcements. Immediately.
Qin Mo did not hesitate.
....
The Battlefield
By the time help arrived, the Imperial defenders had been pushed back to their last refuge.
A bunker.
The outpost around it was gone.
What had once been a fortified perimeter was now a field of craters, collapsed barricades, burning sandbags, and twisted weapon mounts. The heretics owned everything outside the bunker walls. They swarmed through the wreckage in packs, dragging corpses aside only when the bodies blocked their line of advance. Their banners snapped in the hot drafts rising from burning promethium. Their voices rose and fell in chants that sounded almost human until too many throats joined in.
The bunker itself was a low ferrocrete block half-sunk into the underhive floor, reinforced with scrap plating and whatever armor panels the defenders had been able to weld across the entrances. Its firing slits spat lasfire in ragged bursts. Inside, men coughed through smoke, reloaded with shaking hands, and dragged the wounded away from the door because there was nowhere else to put them.
The heretics hurled grenades into the bunker at regular intervals.
Each time, the defenders threw them back.
When they could not, someone dived onto the grenade.
No one ordered them to. There was no time for speeches. A man saw the grenade, saw his squad, understood the arithmetic, and made himself the answer.
Their numbers dwindled.
Minute by minute.
....
After thirty minutes of desperation, the eternal darkness above the underhive was pierced by two glowing spheres.
They descended through smoke and ash like miniature suns, their surfaces burning gold-white as they cut trails through the polluted air. For one impossible second, the battlefield below was illuminated in full: the bunker's cracked roof, the press of heretics around it, the bodies stacked near the entrance, the upturned faces of men who had forgotten what reinforcement looked like.
The spheres detonated one hundred meters above the heretic line.
White light swallowed the sky.
Then the lasstorm began.
Beams rained down in dense, controlled patterns, not random bombardment but deliberate execution. Crimson and white-hot streaks carved through the enemy mass. Flesh flashed to vapor. Bone cracked. Armor plates glowed, softened, and folded around the bodies inside them. Fortified positions became slag-lined pits. Heavy weapon teams disappeared beneath curtains of light before they could turn their guns upward.
The bunker shook under the pressure wave. Dust fell from the ceiling. A wounded defender laughed once, then started crying because his mind had no other way to process the fact that the enemy outside was dying faster than the men inside.
Before the smoke cleared, a deep mechanical hum rolled across the battlefield.
Anti-grav engines whined.
A transport drone descended through the haze, its bulky armored frame shimmering behind layered energy fields. Stabilizer fins adjusted in quick, precise motions as it hovered above the killing ground. Its underside glowed with heat from atmospheric braking. Ash and loose debris spiraled beneath it in widening rings.
The bay doors opened.
Three figures dropped.
They struck the ground with the force of falling statues. Impact shockwaves rippled outward, cracking ferrocrete, throwing dust into the air, and scattering the blood pooled around the landing zone. The earth groaned beneath their arrival.
Qin Mo had arrived. With him stood Grey and an old veteran named Grot.
Grot was a towering man with short brown hair, a scarred jaw, and the thick-necked build of someone who had spent most of his life carrying equipment heavier than common sense. He was one of the surviving Six of the 44th Infantry Regiment, an oath-bound warrior who had pledged to fight at Qin Mo's side until the end of all things. He had the blunt confidence of a man too old to be impressed by danger and too stubborn to admit pain until it became fatal.
All three wore the new armor.
All three carried gravity hammers.
But Qin Mo's Aquila staff remained unchanged.
The staff had become more than a weapon. It was a banner, a lie, a promise, and a convenient way for terrified Imperial soldiers to explain the impossible without asking questions that would get everyone killed.
Inside the bunker, someone saw it through the smoke.
"The Staff!" The cry spread instantly. "It's him! The one the Emperor sent!"
Morale ignited.
The stories had already traveled farther than Qin Mo thought. The western line had been saved by a warrior carrying an Aquila-topped staff. Men who should have died had survived because he had appeared in fire and smoke. In the underhive, rumor moved faster than supply convoys and was usually more reliable.
Now the defenders saw the staff with their own eyes. Exhausted men stood straighter. Wounded soldiers dragged themselves closer to firing slits. Someone began shouting a prayer, and others took it up because faith was easier to hold than terror.
"Call in the fire support drones," Qin Mo ordered. His voice cut through the vox and the open air at once, calm and hard. "We're wiping them out."
Grey and Grot moved without hesitation.
Two massive anti-grav drones roared overhead, each nearly the size of a Valkyrie dropship. Armored panels slid open along their bellies and flanks. Weapon assemblies deployed in sequence with sharp metallic snaps: lascannons, plasma launchers, rotary chainguns, and adjustable bombardment emitters mounted on stabilized gimbals. Targeting lenses burned red through the smoke.
Then they opened fire.
The battlefield ceased being a siege and became an industrial process of destruction.
Explosions walked through the heretic rear line. Lascannon beams punched through barricades and the bodies hiding behind them. Plasma bursts burst against armored knots of mutants, turning them into expanding clouds of steam and meat. Rotary chainguns hammered low across the field, shredding legs, torsos, weapon teams, and anything foolish enough to cluster together.
Heretics disintegrated.
Fortifications shattered.
The bunker defenders stopped firing for several seconds because there was almost nothing left in front of their firing slits that required them.
"Grey," Qin Mo said over the squad channel, his eyes moving across the battlefield with cold precision, "maximize enemy casualties."
Grey's armored helm dipped once.
"Grot," Qin Mo continued, pointing his staff toward a mutant monstrosity looming among the heretic ranks, "eliminate that abomination."
The creature was taller than an ogryn, hunched beneath slabs of swollen muscle and crude metal grafts. Hooked limbs dragged across the ground. Steel tendrils twitched from its shoulders, each ending in blades, clamps, or bone hooks. Its head was buried beneath layers of scar tissue and chitinous growth, leaving only a lipless mouth and several wet, uneven eyes.
"For the Emperor!" Grot roared.
His jump pack ignited.
Fire blasted from the thrusters, launching him across the battlefield in a straight, brutal line. Heretics in his path tried to scatter. The grav-shield hit them first. Bodies collapsed under sudden pressure, bones breaking inward as the expanding kinetic barrier crushed them into the ground. Those not killed outright were thrown aside like rags in a storm.
Grot slammed into the abomination at full force.
The monster shrieked.
"SAAAHHH∼!"
Its hooked limbs lashed out. Steel tendrils snapped toward him, striking the grav-shield hard enough to spark against the distortion field. The shield held, but Grot did not wait for it to absorb the next blow.
He deactivated the field. For half a second, he stood exposed beneath the monster's shadow. Then he swung the hammer.
The gravitational distortion around the hammerhead struck the abomination's skull before the metal itself fully connected. Pressure folded inward. Bone, chitin, and reinforced growth plates compressed with a sound like stone breaking beneath deep water.
There was a brief silence.
Then a wet crunch rolled across the vox. The abomination collapsed. Its skull had become a flattened ruin. Its limbs spasmed once, twice, then settled into the mud.
Qin Mo exhaled through his nose.
"Sigh∼…"
This was not the plan.
They had a new doctrine now. Fire support first. Precision elimination second. Advance only when needed. The armor had been designed to let a few soldiers dominate a battlefield without acting like enthusiastic melee idiots in expensive suits.
Yet even in this new age of warfare, power-armored troops still fought the old way the moment something large and ugly appeared within hammer range.
Grot, satisfied with his kill, planted one boot on the corpse and looked around for the next target. Qin Mo could practically hear the man grinning inside his helmet.
Grey, however, understood the new doctrine.
He had listened while Qin Mo explained energy cycles, drone coordination, bombardment patterns, and shield overlap during the long development sessions. He had listened partly because he respected Qin Mo, partly because he was curious, and partly because he had been the one delivering meals and there was no polite way to leave while Qin Mo was explaining how to revolutionize infantry warfare over ration paste.
Instead of rushing into the enemy mass, Grey summoned an energy drone.
The compact anti-grav unit descended beside him and locked into formation above his right shoulder. A magnetic tether snapped into place. Power indicators flashed across Grey's visor as the drone linked to his armor, smoothing the energy engine's output and opening reserve channels for sustained fire.
Effectively unlimited operational time, so long as the battlefield kept feeding him.
Grey raised his right arm.
His laser scattergun unleashed a storm of light.
The weapon did not fire in a simple cone. It projected a layered burst pattern, each las-beam angled to cover a different lane of advance. Heretics crossing open ground were cut down in rows. Those behind barricades were struck through gaps, through weak points, or through the bodies of the men in front of them.
His shoulder cannon cycled.
Three projectiles launched in quick succession, each one rising in a shallow arc before detonating mid-air. Clouds of las-shrapnel burst outward over a wide radius, scattering downward in precise, murderous rain.
There was no cover.
It did not matter whether the heretics crouched behind barricades, crawled through craters, or hid beneath sheets of scavenged metal. The fragments found them. Men screamed, jerked, and fell apart beneath impacts too small to see clearly and too numerous to survive.
The scorched metal ground beneath them bubbled and warped as heat built faster than the underhive's ancient alloy could shed it. Pools of molten slag formed where defensive positions had stood. Smoke rolled low across the field, thick with ash, vaporized blood, and the chemical stink of burned cult markings.
The bunker defenders emerged slowly, weapons still raised, unable to trust that death had truly moved away from them. They saw three armored figures advancing through fire, drones circling overhead, and heretics dying faster than they could flee. Some fell to their knees. Others simply stared.
Qin Mo watched the battlefield with a creator's dissatisfaction.
The armor worked. The drones worked. The doctrine worked when someone followed it.
But the response times could be better. Drone target allocation still lagged by fractions of a second when enemy formations broke apart too quickly. The shoulder cannon's mortar mode produced more heat bleed than he liked. Grey's energy drone was compensating well, but the tethered transfer rate could be improved. Grot's hammer strike had been effective, but a proper close-combat user needed better discipline cues and a warning system that shouted "do not charge yet" in a voice loud enough to penetrate veteran stubbornness.
Useful data. Costly data, for the heretics.
The battlefield belonged to them now.
And this... was only the beginning.