The Grand Duke's Son Is A Heretic-Chapter 512

The shockwave from Ruth’s burst of power rolled through the underground tunnels like thunder trapped inside stone.

Dust rained down from the ceiling. The dirty canal water jumped and slapped against the walls. The narrow passage, which had felt silent and suffocating moments ago, now felt like the mouth of a battlefield.

Far ahead, deep in the tunnels, answering roars rose.

"They felt that," Elliot said under his breath while tightening his grip on his sword.

Ruth did not turn back. His back stayed straight, and his blade rested over his shoulder.

"Good," he said calmly. "That was the point."

More vibrations came through the stone floor. Something heavy was moving. No, many things.

Kael glanced at Martina. She already held her blade, and her face was serious now, with no trace of teasing.

"Time to go," Kael said.

Ruth gave a short nod."

He pointed to a narrow side tunnel half hidden behind broken bricks and hanging roots. It looked like an old maintenance path, barely wide enough for one person.

Martina stepped in first. Kael followed close behind. Two SS-rank guards slipped in after them.

Behind them, Ruth walked alone into the main passage.

The air in front of him grew darker.

Shapes appeared at the far end. Dozens of abyssal demons rushed toward him. Their bodies were twisted, and their long limbs scraped the walls. Their eyes glowed like coals in the dark.

One shrieked.

Then they all charged.

Ruth exhaled once.

"Come."

His sword moved.

A single horizontal swing cut through the air.

SHHHHHK.

A pale line of light crossed the tunnel. For a moment nothing changed. Then the front line of demons split apart at the waist. Their upper bodies slid off and fell into the canal with wet splashes.

The ones behind crashed into the remains. They climbed over corpses and howled.

Ruth stepped forward into them instead of back.

Sword arcs flashed in the air causing the limbs to fly. Dark blood painted the walls.

Every strike was clean. No wasted motion. He was not rushing, and he was not angry. He was simply cutting.

Deeper in the tunnel, something larger moved.

A heavier presence.

A roar shook the air.

At the same time, Kael and Martina moved through the side passage with Elliot behind them.

This tunnel was tighter and older. The stone blocks were cracked, and tree roots pushed through the ceiling. Rusted pipes ran along one wall, and water dripped steadily from them. The smell here was worse. Stale air, mold, and rot filled their lungs.

Martina covered her nose with her sleeve.

"You were right," she muttered. "This is disgusting."

"I told you," Kael replied quietly.

They moved in single file. Their boots splashed softly through shallow, black water. The tunnel sloped upward little by little.

After several turns, the brickwork changed.

The rough stone became smoother and more even. The tunnel widened slightly. Iron bars appeared along one wall, leading to drainage grates that connected to higher channels.

"We are close to palace infrastructure," Elliot whispered.

Faint light began to appear ahead. It was a pale, steady glow from mana lamps fixed in wall niches.

The air changed too. It was still damp, but fresher. Less decay.

They reached a heavy iron ladder bolted into the wall.

Elliot climbed first and pushed against a circular hatch above. It did not move at first. He pressed again, slowly.

The cover lifted with a low scrape.

Cool air flowed down.

One by one they climbed up.

They emerged into a narrow service corridor beneath the Imperial Palace.

The floor was stone tile, not mud. The walls were carved with clean lines, and faint gold patterns ran along the edges. Mana lamps glowed behind crystal covers. The air smelled faintly of oil and incense instead of sewage.

Far above, through the ceiling, came muffled sounds. Footsteps. Distant voices. The palace was quite guarded.

Water channels still ran along the lower sides of the corridor, hidden beneath metal grates. Maintenance tools hung on hooks nearby. This was a hidden worker passage used by servants and engineers, not soldiers.

Elliot lowered the hatch back into place carefully.

"We are inside," he said quietly.

Martina looked around with sharp eyes, memorizing exits and corners.

Kael adjusted his strange mask and exhaled slowly.

They moved out from the service corridor and into the inner structure of the Imperial Palace.

The scale of the place became clear at once.

High stone arches stretched overhead, carved with old royal patterns now stained with dark marks. Long hallways split into many directions. Wide courtyards opened between wings of the palace, with broken statues and cracked fountains. Mana lamps glowed along the walls, but many flickered, as if disturbed by some dark energy.

Guards were everywhere.

Not just human guards in armor, but abyssal monsters too. Some stood still like sentries. Others crawled along walls and ceilings. Their claws scraped softly against stone, and their low growls echoed through the halls.

Kael and the assassins did not stop.

They moved like shadows.

One guard turned the corner.

Before he could speak, a hand covered his mouth and a blade slid across his throat. His body was lowered gently to the floor.

An abyssal creature dropped from above.

Kael stepped forward, grabbed its jaw, and twisted. A crack sounded, and the body went limp.

They kept weaving through pillars, broken walls, and side passages. Every few steps, another enemy fell silently. Blood stained the floor in thin lines, but no alarms rose yet.

Still, there were too many.

More patrols passed through intersections. More monsters gathered near staircases and main doors.

Elliot stopped near a large hallway that led deeper inside.

He watched two patrol groups cross paths ahead. Then another group came from the side.

His expression hardened.

"We can’t go on like this," he said quietly.

Kael and Martina turned to him.

"I will act as the bait. You two go on and finish the job."

Martina frowned. "Sir—"

Elliot raised his hand.

"Once you are done, blow that triumph horn. Also remember to stay guarded. Your lives are more important than the plan. We can escape even if it fails, but don’t try to overdo it."

His eyes stayed firm. There was no hesitation in him.

Kael nodded slowly.

"Okay. Take care, Sir Elliot," Martina said, her voice low but steady.

Elliot gave a short nod back. Then he stepped out into the open hallway on purpose.

His aura flared just enough to be noticed.

An abyssal monster shrieked.

Guards turned around, alerted and shouted,"There are intruders."

"There!" one shouted.

In the next second, Elliot rushed forward, blade flashing, drawing every eye toward himself.

At the same moment, Kael and Martina moved.

Their figures blurred and vanished into the side passage, slipping away from the growing chaos behind them.