The Death Knight Commander moved with terrifying speed for something so heavily armored. It swung its massive crimson claymore in a wide horizontal arc. A crescent wave of red sword-aura erupted from the blade, slicing through the air with a deafening screech.
Three of Elias's Shadow Knights caught the brunt of the attack. Their shadowy armor was cleaved cleanly in half, and their upper bodies dissolved into black mist.
But Elias didn't blink. "Reform," he whispered.
Instantly, his mana drained, and the black mist violently pulled itself back together. Within two seconds, the three Shadow Knights were fully restored, charging back into the fray without missing a step.
The Death Knight's glowing red eyes flared in what looked like frustration. It raised its claymore to strike again, but a massive shadow eclipsed the ceiling lights above it.
Iron descended.
The Elite Hobgoblin Chieftain brought his heavy battleaxe down with the force of a falling meteor. The Death Knight raised its claymore to block.
CLANG!
The shockwave cracked the stone floor beneath them. Iron's pure brute strength was enough to make the Level 20 Dungeon Boss bend its knees.
"Now!" Elias shouted.
The nine Shadow Knights swarmed the Boss. They didn't attack with their swords; instead, they threw their bodies onto the Death Knight, grabbing its arms, its legs, and its armor. They acted as living, shadowy chains, completely immobilizing the Dungeon Master beneath a mountain of dark bodies.
The Death Knight roared, flaring its crimson mana to shake them off. The shadows began to evaporate under the intense heat of the red aura.
Elias knew he only had a few seconds before his mana pool was completely depleted from regenerating his army. He tightened his grip on his steel crowbar, channeling every last drop of his remaining mana into the crude weapon until it vibrated violently in his hands.
He dashed forward, leaping onto the back of one of his kneeling Shadow Knights, using it as a stepping stone to launch himself high into the air.
The Death Knight looked up, struggling against Iron's axe and the pinning shadows. It exposed the smallest gap in its silver armor—the dark visor of its helmet.
Elias fell like a spear. With a vicious, guttural shout, he drove the steel crowbar straight through the narrow slit of the Death Knight's visor, burying the metal deep into the skull beneath.
The crimson light in the Boss's eyes flickered, then violently exploded.
A shockwave of raw energy blasted Elias backward. He landed gracefully on his feet, panting heavily. The crowbar had melted into slag, and the Death Knight Commander stood frozen for a moment before its massive silver armor collapsed onto the stone floor with a thunderous crash.
[You have slain the Death Knight Commander (Dungeon Master).] [Quest Complete: Clear the Dungeon.] [You have leveled up!] [You have leveled up!] [You have leveled up!] [You have reached Level 15.]
The notification screens flooded Elias's vision, but he ignored them, his eyes locked on the glowing blue crystal resting on the throne of skulls behind the fallen Boss.
He walked over and picked it up. It was cold to the touch and pulsed like a living heart.
[Artifact Acquired: Heart of the Abyss (Epic Grade)]
Effect: Permanently doubles the user's maximum Mana capacity. Increases Mana Regeneration rate by 300%. Shadow Soldier regeneration cost is reduced by half.
Do you wish to absorb the Heart of the Abyss? (Yes/No)
"Yes."
The crystal dissolved into a liquid blue light that seeped directly into Elias's skin. A rush of pure, icy power exploded within his chest. The exhaustion from the fight vanished instantly. He felt as though a dam inside his soul had just burst open, flooding his body with limitless energy.
[Mana: 800/800]
With this artifact, he was no longer a fragile summoner. He was a perpetual motion machine of death.
Elias turned his attention back to the massive silver-armored corpse on the floor. Thick, jet-black smoke, laced with crimson lightning, was pouring out of the armor. The sheer density of the soul was suffocating.
[An Elite-Tier soul has been detected. Would you like to extract the shadow? (Yes / No)]
"Arise."
The room trembled. The black and crimson smoke spiraled upward, shaping into a towering, terrifying knight. It was clad in pitch-black plate armor, a shadowy tattered cape billowing behind it. In its hands, it held a massive claymore made of dark, swirling energy.
[Extraction Successful!] [Commander Grade Shadow: Death Knight (Lv. 20) has joined your legion.]
Elias stared at the magnificent creature. A 'Commander Grade'. In his past life, Hunters would pay billions to have a Level 20 tank in their guild, and Elias had just acquired one that couldn't be killed and didn't need to be paid.
"Your name is Blood," Elias said, looking at the crimson aura radiating from its sword.
The Death Knight Commander dropped to one knee, bowing its head deeply to its new monarch.
[The Hidden Dungeon has been cleared. The portal will close in 5 minutes.]
Elias recalled his entire army into his shadow. The stone cavern fell completely silent, empty except for a lone young man who had just secured his place as the strongest being in the city.
He walked back toward the glowing blue exit portal. It was time to return to the surface. It was time to see how the rest of the world was coping with the apocalypse, and more importantly, it was time to cash in his loot.
As Elias stepped through the portal, the blue light engulfed him, and the Dungeon of Echoes collapsed into nothingness.