I Was Summoned as the Weakest Hero, But I Awakened a Military System

On the shattered deck, the situation was turning hopeless.

The ship tilted past fifty degrees. Brine poured over the gunwales in roaring sheets, dragging barrels, ropes, and screaming imperial sailors into the churning sea. The remaining wind mages collapsed one by one, clutching their heads as severe mana exhaustion took hold. Without their magic, the forced gales died completely. The ship was dead in the water.

”Hold the line!” Captain Daniel coughed, swinging his broadsword at a smaller tentacle that whipped across the deck. The blade struck the thick hide, sending sparks flying, but it barely cut through the tough skin. The backswing of the limb struck Daniel full in the chest, hurling him across the broken deck into the collapsed wheelhouse.

”Captain!” Miyuki cried out.

She tried to push herself up, but her legs trembled violently. Her wooden staff had splintered near the grip, and the glowing green gem at its head flickered with weak, fading light. Her mana pool was nearly empty from casting non-stop barriers and physical enhancements.

The Kraken squeezed tighter. Long fractures groaned through the thick oak keel. The lower hull was caving in, seawater rushing into the cargo holds with a terrifying gurgle.

Ayanokoji stood between Miyuki and the monster’s looming head. His light armor was cracked across the chest, and deep bruises covered his arms. Even with his high S-Class physical stats, he was hitting a hard wall. His spear was sharp, but cutting through hundreds of tons of regenerative meat with a five-foot polearm while balancing on a sinking splinter of wood was mathematically impossible.

Three tentacles rose together, blocking out the starry sky above them.

”Miyuki,” Ayanokoji said, his voice quiet, still devoid of panic even as the shadow fell over them. ”Can you cast one last air cushion to throw us toward the second corvette?”

Miyuki looked toward the sister ship. It was three hundred meters away, desperately turning its rudder to escape the whirlpool, entirely unable to help.

She looked down at her shaking hands, tears pricking the corners of her eyes. ”I... I don’t have enough mana left. Ayanokoji, I can’t even cast a basic barrier.”

The monster let out an ear-piercing shriek, its beak clicking wide open. The tentacles whipped down like falling iron pillars, ready to pulverize the deck and everyone on it into paste.

There was no way out.

Miyuki lowered her head and closed her eyes, bracing for the bone-crushing impact, silently waiting for the darkness to take her.

THOOOOOM.

It wasn’t the sound of wood shattering.

It was a deep, catastrophic detonation that came from deep under the ocean surface.

The entire sea violently shuddered. A massive underwater shockwave tore through the water, followed by an enormous plume of white foam, boiling steam, and black water that erupted forty yards from the corvette’s hull.

The Kraken’s deafening shriek suddenly twisted from pure malice into sheer, unadulterated agony.

Under the water, a high-explosive warhead had slammed directly into the monster’s soft underbelly. Over six hundred pounds of high-grade explosive tore through its rubbery armor, ripping through internal organs and vaporizing thick muscle into burning red chum.

The massive tentacles instantly released their death grip on the corvette. The beast violently spasmed, flailing its remaining limbs in absolute panic as boiling blue and purple blood gushed into the sea, turning the water into a dark, burning slick.

Miyuki opened her eyes in shock, stumbling as the ship righted itself slightly. ”What... what was that?!”

Ayanokoji narrowed his eyes, staring down into the black water where the explosion had originated.

”It wasn’t magic,” Ayanokoji muttered.

Terrified by a force it couldn’t comprehend, the wounded Kraken turned its massive body and dove straight down into the deep, desperately trying to escape into the dark abyss.

Four hundred feet below, inside the silent control room of the USS Montana, low crimson lights illuminated the consoles.

”Direct hit on the biological target,” Miller reported calmly into his headset. ”Target took heavy structural damage to its lower mantle. It’s breaking off and diving fast toward eight hundred feet. Speed dropping to twelve knots.”

Commander Gallagher stood behind the fire control station, his hands resting easily on his hips. The phone line to Eagle Actual had just clicked shut.

”It thinks it’s the apex predator down here,” Gallagher said, a cold, predatory smirk touching his lips. ”Let’s remind it where it sits on the food chain. Tube two, load Mark 48 ADCAP. Match bearing and depth. Flood tube two.”

”Tube two flooded, outer doors open, Captain,” the weapons officer replied smoothly. ”Target acquired on active acoustic homing.”

”Fire tube two,” Gallagher ordered.

”Tube two, fired.”

A heavy jolt passed through the submarine’s hull as the high-speed wire-guided torpedo shot out from the tube, churning through the black depths at fifty-five knots, homing directly in on the wounded monster.

The Mk 48 tore through the frigid water, its pump-jet propulsor leaving a tight trail of micro-cavitation in the dark. The sonar array in its nose pinged steadily, locking onto the deafening biological thrashing ahead.

Six hundred feet down, the Kraken pumped its remaining siphon, desperately pushing itself toward the abyssal trench. But an organic leviathan, even an S-rank horror of this world, could not outrun an apex machine designed to kill nuclear submarines.

”Weapon running hot, straight, and normal,” Miller reported, watching the green trace close the gap on his waterfall display. ”Distance five hundred yards... three hundred... terminal homing sequence initiated.”

The torpedo slammed cleanly into the beast’s upper mantle.

BOOOOOOM.

The detonation hollowed out the ocean. A concentrated shockwave shattered the creature’s internal organs and pulverized its nervous system, instantly killing the regeneration. Chunks of charred hide and vaporized flesh scattered into the freezing currents.

”Good job boys, target is neutralized,” John announced.

”Thank you for the confirmation, Eagle Actual,” Gallagher said and added. ”Secure from firing stations. Bring us up to periscope depth. Let’s see what’s left of our guests up top.”

On the surface, the sea suddenly calmed, the massive whirlpool collapsing into gentle swells covered in floating debris and blue gore.

Ayanokoji stood on the listing deck, leaning on his spear as he stared into the black water. His sharp mind pieced the variables together.

Even then, he doesn’t understand what monster was attacking the Kraken from below the sea.