Bloodbound Codex: I Grow Stronger in Secret

The underground ruin trembled faintly as dust fell from the cracked ceiling.

The corpses of several Hybrid Muxicals surrounded the battlefield, their blood spread heavily across the black stone beneath the Revenants’ feet. The Royal Revenants had already cleared the first wave, but no one relaxed after that.

Because ahead of them stood the Ulgroth.

Its massive body towered over the shattered battlefield. Dark gray fur covered layers of dense muscle, and seven enormous tails moved behind it with slow, controlled rhythm. Its crimson eyes remained fixed on the Revenants, not with simple hunger, but with intelligence.

That was what made it dangerous.

A beast attacked because it wanted to kill or feed.

An evolved spiritual monster could calculate.

The pressure coming from the Ulgroth was enough to make even the S-Rank Revenants tense. They knew exactly what stood in front of them. One wrong step, one delayed reaction, one failed defense, and death would come before they could correct the mistake.

The Ulgroth lowered its massive body.

Its claws dug into the black stone.

Then it vanished.

At least, that was how it looked to most of them.

Several S-Rank Revenants widened their eyes instantly. They could not follow the movement. No sound reached them. No clear presence shifted. No visible path remained. The creature had simply disappeared from where it stood.

Too fast.

Far too fast.

Even among S-Rank monsters, this Ulgroth stood near the peak.

But two people remained calm.

Velmira.

And Mark.

Velmira stood with her arms crossed, her crimson eyes observing the battlefield without interruption. She was not surprised by the Ulgroth’s speed. That alone told the others she had already measured the creature differently from them.

Mark stepped forward slowly.

His expression remained relaxed, almost detached. His black combat attire fluttered faintly from the wind pressure left behind by the Ulgroth’s movement, and the golden insignia on his chest reflected dimly under the ruin’s ancient glow.

But something about him felt strange.

No Spirit pressure leaked from his body.

None.

For a Revenant, that was abnormal. Even when suppressing Spirit Energy, a faint trace usually remained. Mark had sealed his presence so completely that he almost felt empty. Whether that was a technique, a relic, or something else, the others could not tell.

Then the Ulgroth appeared.

It was an inch away from Mark.

Its massive claw had already descended by the time most Revenants processed its position. The curved black nails tore through the air toward Mark’s skull with enough force to split reinforced steel.

Several Revenants reacted too late.

Mark did not.

His eyes were closed.

The claw approached.

Closer.

Then Mark tilted his head slightly.

Shhk.

The claw passed beside his face and missed by less than a finger’s width.

The force behind the strike tore through the ground behind him, carving deep marks across the black stone and throwing rubble into the air. Mark’s feet did not move. He had avoided the strike with the smallest possible motion.

The Ulgroth’s crimson eyes narrowed.

It attacked again.

Another claw came faster.

Mark shifted his body by a small amount.

The claw missed.

Then came another strike.

And another.

And another.

The Ulgroth unleashed a continuous barrage. Its claws blurred through the air, tearing apart the battlefield and sending shockwaves through the underground chamber. Each strike had enough power to kill an S-Rank Revenant if taken directly, so the others retreated farther without needing an order.

They understood the difference now.

This was not a fight they should interrupt.

Yet inside the storm of attacks, Mark avoided everything.

His eyes remained closed.

His breathing stayed steady.

No wasted movement and no Spirit Energy.

Velmira observed him silently from behind.

Then a faint smile appeared on her lips.

”He’s improving.”

One nearby Revenant glanced at her with disbelief.

Improving?

Against that?

But Velmira’s assessment was not casual. Mark was not merely dodging. He was using the Ulgroth’s movement to refine his own reaction timing. Each dodge became smaller than the last. Each adjustment used less motion. The creature was attacking with overwhelming speed, but Mark was turning the exchange into training.

The Ulgroth grew more violent.

Its seven tails slammed against the ground, and its movements accelerated further. The pressure from its physical body cracked nearby pillars, and the shockwaves from its missed attacks tore deeper into the chamber floor.

Then Mark moved properly for the first time.

His eyes opened.

Sharp gray pupils locked onto the descending claw before him.

His right hand rose calmly.

And caught it.

BOOOOM.

The battlefield exploded from the impact.

Black stone shattered beneath Mark’s feet, and the shockwave swept across the chamber hard enough to force several Revenants backward. Yet Mark remained standing, one hand holding the massive claw in place.

The Ulgroth’s eyes widened slightly.

Its claw had stopped completely.

Mark’s expression remained indifferent.

”...Too much unnecessary movement.”

His voice echoed softly.

Then his grip tightened.

Crack.

Bone broke.

The Ulgroth roared in pain as its massive claw twisted unnaturally under Mark’s physical strength.

This was pure physical force.

Several Revenants felt chills crawl down their spines.

Even they could not replicate that.

Then Mark moved again.

His body disappeared from sight.

The Ulgroth’s instincts reacted instantly.

Danger sense flared.

It tried to retreat, but it was too late.

Mark appeared directly beneath its chest.

His fist drew back slowly.

A simple stance.

Then he punched.

BOOOOOOM.

The impact detonated.

The Ulgroth’s gigantic body lifted off the ground and crashed through multiple ancient pillars behind it. Black stone shattered one after another as dust clouds exploded throughout the chamber. The entire ruin trembled from the force.

Several Revenants stared silently.

One punch.

Just one.

And an S-Rank evolved monster had been launched across the battlefield like dead weight.

Mark lowered his fist.

His face was still expressionless.

But his eyes had become colder.

Velmira narrowed her gaze at his back.

She noticed it again.

That slight hesitation buried beneath his movements. Mark was fighting properly, but his attention was not fully on the battle. Part of him was elsewhere.

She narrowed her eyes for a moment.

Then the rubble exploded outward.

The Ulgroth emerged again.

Blood poured heavily from its mouth, and one of its arms hung broken beside its body. Yet the creature did not retreat. Instead, its monstrous mouth stretched into something close to a grin.

Crimson Spirit Energy erupted from its entire body.

The pressure in the chamber multiplied instantly.

Several Revenants felt their breathing stop for a moment.

”...It evolved further?” one muttered.

Velmira’s eyes sharpened.

”No.”

Her voice turned colder.

”That thing was hiding its true strength.”

The Ulgroth’s seven tails rose at the same time. Dark crimson energy spiraled around them, and the surrounding stone began cracking beneath the pressure.

Then the creature spoke.

”...Humans...”

The distorted voice echoed through the underground chamber.

Every Revenant froze.

Because monsters should not speak.

The Ulgroth’s crimson eyes locked onto Mark.

”...You smell...”

Its grin widened slightly.

”...interesting.”

Silence fell.

Even Mark’s calm expression shifted slightly for the first time.

And far behind the battlefield, hidden beneath the shadows of a broken pillar—

something else opened its eyes.