Martial Arts were the unique abilities of warriors in this world, the equivalent of magic for fighters.
Activating a Martial Art consumed Concentration, the manifestation of one's mental focus. Repeated use placed a heavy burden on the mind, causing intense fatigue.
If someone forcibly activated a Martial Art beyond the limits of their Concentration, their body would collapse and they could even die within a short time.
Different Martial Arts required different amounts of Concentration. The higher the tier, the greater the cost.
Unlike magic, however, multiple Martial Arts could be activated simultaneously and combined into composite techniques, producing a result greater than the sum of its parts.
Another advantage was stacking.
With magic-based enhancements, only the strongest effect would remain active.
Martial Arts were treated as separate effects and could accumulate. That meant two similar enhancement techniques could be layered for greater power.
For example, the Martial Arts [Ability Boost] and [Greater Ability Boost] could be used together, amplifying one another.
In contrast, if the spells [Low-Tier Attribute Boost] and [High-Tier Attribute Boost] were cast at the same time, only [High-Tier Attribute Boost] would take effect. The lower-tier spell would be overridden.
Herohero found Martial Arts fascinating. The enhancement they provided was not dramatic, but they required no mana.
That alone made them valuable.
After all, in the game Yggdrasil, there were no blue potions. Players could only recover mana through natural regeneration.
The original setting was exactly that, though cash items such as the Bone King's [Shooting Star Ring] could restore resources by activating Super-Tier Magic.
[Increase In Focus Capacity]
This was Brain's Talent. It directly affected Concentration, the very foundation required to activate Martial Arts.
For Herohero, who had come to this world from elsewhere, this Talent was like a key that opened the door to Martial Arts.
"Unlike mana, it's entirely driven by mental energy. How intriguing."
Outside the cave, beneath the cold moonlight, Herohero extended an arm. Multicolored light shimmered faintly across his body.
[Ability Boost]
[Greater Ability Boost]
Drawing on the memories he had absorbed, he successfully activated the Martial Arts. A peculiar energy flowed through him, strengthening his body from head to toe.
"It's a slight increase."
Herohero clenched his fist and carefully assessed the change.
If his strength had been 100 before, it was now roughly 105. The improvement was subtle, but undeniably real.
"Let's go, Shalltear. It's time to head back."
After testing the techniques a bit more, he stopped. Further experimentation could wait until they returned to Nazarick. It would also give him something to show off to Naohara and Momonga.
"As you command."
Shalltear reluctantly withdrew her hand from the Vampire Bride she had been toying with. She was about to say something when she suddenly froze.
Her dark crimson eyes shifted toward a certain spot in the forest.
A brilliant light flared in the distance.
"Herohero-sama, my subordinate has been slain."
Her expression twisted instantly, anger flashing across her face. For a moment, it seemed as though she would lift her skirt and charge toward the light without hesitation.
But because Herohero-sama was present, she restrained herself.
If Demiurge had been here instead, she would have already rushed out.
"Slain?"
Herohero was slightly surprised.
The subordinate had only been stationed there to prevent any bandits from escaping, but its strength was comparable to the so-called Hero-class warriors of this world.
For it to be eliminated so easily was unexpected.
But Herohero quickly calmed down. The more critical the situation, the less he could afford to panic. Right now, information was everything.
"Send more Familiars. I want detailed intelligence on them."
"And calm yourself, Shalltear. Don't let anger cloud your judgment."
"Hah… This servant understands!"
Shalltear drew in a deep breath, forcibly suppressing the fury boiling inside her. In front of a Supreme One, she could not allow herself to appear unsightly.
She activated the spell [Summon Familiars]. In an instant, a tide of dark monsters surged forth. At the same time, she commanded all remaining Familiars within the forest to rush toward the site of the disturbance.
"What's the situation?"
After waiting a moment, Herohero asked.
"There are twelve in total. Well-equipped. Most of them are above level 30, but one surpasses even Solution, approximately level 70."
"And among them is an old woman… I sensed a dangerous aura from her."
Shalltear slowly opened her eyes, her expression grim.
Herohero's body stiffened at her words. He did not doubt her, yet it was still hard to believe. For Shalltear to feel danger, the opponent would normally have to be at least level 100.
"Who is it?"
He searched through his memories, considering one possibility after another, only to dismiss them all.
While Herohero was deep in thought, Shalltear suddenly frowned slightly.
"Herohero-sama, something seems off. The old woman who made me feel that danger hasn't taken action against my Familiars."
"And the others appear to be deliberately protecting her. They're extremely cautious when facing the Familiars' attacks, completely on the defensive. It even looks like they're preparing to retreat."
"Retreat?"
Herohero paused. Something about this truly felt wrong. If there was someone capable of making Shalltear sense danger, why would they retreat?
If it were him, he would have already slaughtered those Familiars. Retreating simply did not make sense.
Unless it wasn't that they didn't want to act… but that they couldn't.
He recalled what Shalltear had said earlier. She sensed danger. If that danger did not come from the person herself, then…
A bold guess surfaced in Herohero's mind. The three of them had once speculated that perhaps they were not the only ones who had crossed over. And now, there was a presence that could make Shalltear feel threatened.
"Players… World-Class Items."
The thought surfaced hesitantly, but it was the only explanation that made sense.
"Shalltear, you only said you sensed a dangerous aura, correct?"
He looked at her meaningfully.
"Yes. Is there a problem, Herohero-sama?"
"That's it. If you sensed danger, yet they chose to retreat, then this is the only possibility."
Having confirmed his suspicion, Herohero's slime-like body trembled. His jet-black tentacles flailed about, revealing the intensity of his emotions.
"What do you mean?"
Seeing Shalltear's confusion, Herohero activated [Black Heart] to steady himself before continuing.
"If they're retreating, it means that old woman herself isn't strong. But she still made you feel danger. If it's not her strength, then there's only one explanation left."
"She's carrying a World-Class Item. That would explain everything."
"World-Class Item!"
Shalltear trembled, her voice shaking.
Of course. Even if the opponent was weak, simply carrying a World-Class Item would be enough to make her sense danger. A lethal kind of danger.
There were only two hundred World-Class Items in existence, each said to possess power rivaling an entire world.
"Shalltear, keep them occupied. Under no circumstances can they be allowed to escape."
Herohero's tone was grave. With a World-Class Item involved, he could not afford the slightest mistake.
Shalltear nodded seriously and began casting spells one after another, continuously summoning more Familiars.
[Message]
After confirming the situation, Herohero immediately activated his Message to contact Momonga in Nazarick.
"Hmm? Herohero? Calling me this late, what's the matter?"
"Don't tell me you want to play cards, haha."
Momonga joked lightly, but Herohero's next words made him freeze.
"Momonga, this is extremely urgent. Bring all of Nazarick's Guardians at once. Retrieve the World-Class Item from the Mausoleum and rendezvous with me in the forest outside E-Rantel."
"I've discovered a suspected Player. They may be carrying a World-Class Item."
"…What?"
In Nazarick, Momonga had been painstakingly reviewing documents. He paused in shock. A faint green glow flickered around him, snapping him back to full alertness.
"Are you certain?"
His tone turned solemn, the red points of light in his eye sockets flickering.
"Eight or nine times out of ten."
"Understood. Herohero, hold them there. I'm leaving immediately."
"Alright. Inform Naohara for me. This place is close to E-Rantel. I'm worried they might intercept the Message."
"Got it. I'll have Albedo notify Naohara."
After ending the Message, Momonga clenched his skeletal fists tightly. A terrifying aura radiated from him.
"Players… and World-Class Items?"
"Whatever they are, they had better not disturb our lives…"