The engine decks of the Arcadia were a cathedral of power. Great plasma conduits pulsed with blue light, their hum a heartbeat felt in steel and bone alike. The Dark Matter Drive lay deeper still, hidden within vaults of unmarked alloy, its presence sensed more than seen — a low thrum that pressed against the skull, half-myth, half-reality.
To the Arcadians, it was sacred.
To the Mechanicus, it was heresy incarnate.
The invaders came like a tide. Boarding doors burst open under the hiss of plasma cutters, Skitarii storming through with rifles blazing. Enginseers marched at their head, binharic canticles pouring from their vox-grilles, each syllable a knife in the ears of Arcadian engineers. Servitors followed, their heavy bolters and flamers roaring in the tight corridors, reducing men to ash.
"Secure the conduits! Bring the unblessed engine to silence!" a Magos bellowed, its voice layered with static. Half its body was steel, cables and augmetics writhing in place of arms. A glowing staff crackled with arcs of power as it strode forward, its eyes burning crimson through a mask of bronze.
Arcadian engineers fought like demons.
Clad in oil-stained overalls, wielding spanners, welders, and antique laspistols, they stood against the machine tide. They knew the ship better than any outsider ever could — sealing plasma conduits, rerouting energy surges, venting whole compartments into the void to purge invaders.
But the price was steep.
One crewman, bloodied but unbroken, slammed a wrench into a plasma regulator, locking it open until it burst in a flood of white-hot fire that consumed both him and the Skitarii squad charging the conduit. Another sealed himself inside a coolant chamber, luring servitors in before overloading the system and drowning them all in freezing cryo-slush.
Every inch of corridor was bought with lives.
The Arcadia herself fought alongside her crew. Bulkheads slammed shut in perfect rhythm with Harlock's commands. Mist boiled through the corridors, confusing targeting augurs. Deck plates twisted beneath the Skitarii, sending them crashing into venting plasma streams.
Yet still, the Mechanicus came.
Harlock arrived on the central engine deck as the Magos breached the inner sanctum. Sparks burst around him as the colossal doors fell. His crimson eye glowed beneath his patch, saber sparking arcs of lightning in his grip.
The Magos turned, staff raised high. "Captain Harlock. Francis Horlock. You are an anomaly to be erased. This engine is an affront to the Omnissiah. I shall return it to blessed silence."
"You'll have to kill me first," Harlock said coldly.
"Such was the calculation," the Magos replied.
The duel erupted in a storm of light.
Harlock's saber screamed arcs of energy with every strike, carving through augmetic limbs and sending sparks flying. The Magos countered with its staff, discharging bolts of searing plasma that scorched the deck around them. Each blow was titanic, steel groaning as power clashed against power.
Skitarii swarmed to support their master, but the Arcadians surged with them. Men and women threw themselves into the melee, cut down by galvanic fire but dragging invaders into death with them.
"Hold the line!" Thomar roared, axe dripping with blood and oil. "For Arcadia! For the Captain!"
The fight dragged on, brutal and relentless. Harlock's crimson eye burned, seeing strikes before they landed, guiding his blade with preternatural precision. He slashed, severing one of the Magos' mechadendrites in a spray of sparks.
The Magos reeled, vox-grille screeching. "You are taint made flesh. The Omnissiah shall not suffer you to live!"
"Then tell Him yourself," Harlock snarled, driving his saber into the Magos' chest. Lightning exploded from the blade, coursing through the priest's body. The Magos screamed, a sound like tearing steel, before collapsing in a heap of smoking metal.
The Skitarii faltered. The Arcadians surged.
The engine decks ran red with blood and oil, but the Dark Matter Drive still throbbed, untouched, alive.
And as the survivors raised their weapons, breath ragged, they knew what they had done.
They had held the heart of their ship.
They had bled to keep it beating.