Netherborne [An OP Monster Isekai]

Alice floated beside Victor with raven mana flowing across the surface of her skin—it almost looked like a bucket of black tar had been poured over her as wisps of purple flame wrapped her fingers, ready to be unleashed at a moment’s notice. Her face was concealed, leaving no point of weakness as they faced an unknown threat.

The dull castle wall, nestled a few meters inside a cave, was merely a front to something else—a home. A mana signature so dense it could belong to Hyveth Arcspace emanated from beyond the castle walls.

Was it a beast of unknown origins? Or maybe mana left behind from an ancient relic? Victor couldn’t answer these questions without an investigation—but was disturbing something with such a presence a good idea?

“Should we?” Victor asked his traveling companions. Entering the home of something that powerful unannounced was a likely death sentence. Nevertheless, curiosity was hard to suppress, especially after a slew of mind-numbing weeks.

Genus slowly crawled back like a terrified cat. “Absolutely not. Whatever lurks in there is far more powerful than any of us. We would be at its mercy, and if it decided to kill us, that would be the end of our story.”

Alice hummed in agreement. “Mhm. What Genus said is correct. Sometimes it’s best to accept there are bigger fish and leave them in their ponds. No need to disturb something like that…”

Victor tried to think back to the many s he had read. His significant advantage is knowing what others did and how best to replicate the successes and avoid the failures. But, as he sifted through his memories, a common theme emerged. Plot armor.

In situations where the protagonist was presented with an unprecedented opportunity, it only ever went well. The question was if he was willing to bet his life on a concept so…abstract. It reminded Victor of Russian roulette, except the gun was empty of bullets. No matter how much someone tried to convince him the chamber was empty, the cold steel of an empty weapon pressed against his head would make him nervous. as if something could go horribly wrong—maybe they left a bullet in.

Victor stared at the castle wall giving off an ominous vibe and ran through the pros and cons. The likelihood of there being a powerful creature that would kill them on sight or a sleeping demi-god that was hellbent on annihilating all undead was relatively high—but on the other hand, if it was some inheritance or relic from a forgotten era, then it could change everything…

What if it can solve my falling stats?

That was the big question. If whatever was past those walls could solve Victor’s biggest life problem and he simply floated onto the final floor, he would regret it. Possibly forever.

The mood had turned grim as Genus and Alice awaited Victor’s verdict on the situation. The mana flowing from those walls is insanely high, but I should be stronger than whatever is waiting within. Victor’s curiosity was far too great, and his willingness to bet on plot armor drove him to a final decision.

“I don’t see an obvious entrance, and the mana is far too dense for me to use Spirit Movement to bypass the wall.”

“Stop.” Genus bared his teeth and raised his neck. The house-size golden dragon glared at Victor with his rainbow eyes. “Do not. Please.”

Victor looked at Alice; she decided to remain deathly silent.

She has faith in me… Victor faltered. This decision concerned himself and the lives of his travel companions. He had to be absolutely sure this was the right move.

“Get ready to run.” Victor just couldn’t shake off his curiosity. Why was a castle wall clearly built by a sentient creature on the seventy-first floor? They had seen no evidence of any Delvers throughout their descent, and this was by far the oddest thing they had encountered. To turn away and pretend like they saw nothing was ridiculous and would eat away at his mind like an unscratchable itch.

Genus didn’t even wait for Victor to finish his instructions. He had already spread his wings and, with a mighty flap, vaulted into the sky, leaving a cloud of gems and a crater in his wake.

Alice didn’t speak, but she gave him a nod.

Victor consumed five million stat points and began charging up a Doom Ray. Mana swirled around his fingers, boiling his intangible, shadowy flesh.

Alice also silently raised her hand, a javelin of black ice forming from her outstretched palm like an arrow waiting to be released.

Purple lightning crackled between Victor’s claws as he prepared his attack. Still no movement… Victor had a slight suspicion that whatever resided within those walls was either asleep or dead. They should have detected their presence when they arrived, and now with two high-tier spells being cast on their doorstep, to still not show themselves was suspicious.

Deciding the chance of survival outweighed the likelihood of death, Victor aimed his hand like a particle cannon—gestured for Alice to fire her spell first—and then unleashed the most powerful Doom Ray he had ever mustered. The world turned rainbow as the explosive light expanded and reflected off all the millions of gems lining the landscape. Like being inside a prism, Victor’s senses were overloaded with color, and then with a snap of his claw, the spell ceased, and an ear-shattering explosion followed the tremors of the land.

Superheated rock was buried under a landslide as half the mountain tumbled. The various natural ores making up the mountain melted into a soup that surged with the landslide like a tsunami.

Victor floated back to a safe distance and waited. He watched alongside Alice from the air as the metal soup rapidly cooled and mixed with all the gems, creating a dazzling piece of art.

Time passed. Nothing emerged from the cave.

Victor mentally commanded Wiggles to tunnel through the molten rock to where the castle wall had been. The ground trembled again, and gems cascaded off the titanic earthworm’s back as he surfaced. His teeth became coated in neon saliva that melted the metal as he chomped his way through. The process was slow, but Wiggles had penetrated a few miles through the landslide after an hour and encountered the wall.

Deciding to take no chances, Victor told Wiggles to retreat and decided to send Henry in. Compared to Wiggles, the apocalypse horseman was far more expendable, cheaper to replace, and could convey more detailed information over their connection. Sadly, due to Henry’s ground-based abilities—and Victor opting for air travel—the poor undead had little to do these last few floors and was likely more bored than Victor.

Henry was happy to accept the order, and after being dropped off on the ground by his dragon mount, he dashed through the spacious tunnel left behind by Wiggles. His hooves echoed through the metal tube as he made quick progress and, before long, arrived at the desired location.

Through Henry’s eyes, Victor saw the castle walls. Surprisingly the only part of the damaged wall was the part Alice’s void mana spell had impacted. All Victor’s spell had done was widen the hole from a few inches to a few meters.

Receiving the go-ahead, Henry slowly trotted his way through the hole. His spear was pointed forward, and his breathing slowed. Other than the occasional popping from air being superheated by the smoldering rock, the space past the castle wall was deathly silent.

The castle wall was a few meters thick, and Victor noted through the connection that the wall was either an illusion or fake. The inside casing of the wall was a dull green metal—certainly not gray stone. Henry made his way through the hole and onto the other side.

“What the hell is that doing here?” Victor exclaimed, and Alice tensed beside him. Her mana shield had relaxed slightly and now showed her anxious face.

“What is it?” she pressed. Victor rarely freaked out like that, so it must have been something shocking.

“It’s…a computer. An old one likely made long ago. Still has the box monitor surrounded by aged plastic.”

“A what? Computer?” Alice tried to remember if such a thing had ever gone through the auction house, but she had never heard of such a thing. Maybe it was a relic from the void?

Through the connection, Victor checked out the rest of the room. It was a rather massive space, surrounded by dull green metal on all sides. He found it impressive that the room was structurally supporting an entire mountain above it and not showing any signs of struggling.

Apart from the old computer that sat on a simple wooden table, there was nothing else.

“Approach it,” Victor commanded, and Henry obeyed. The horseman cautiously approached the foreign object. It radiated off an immense amount of mana in waves as if supplying the entire floor itself. The screen was on, showing a single line of blue text on an otherwise black screen in a text that Henry didn’t recognize, but Victor did.

[Login]

“Step back. Don’t touch it.” Victor rushed toward the tunnel, and Alice quickly followed. There was no way he would allow Henry to inherit or gain anything. He needed it for himself.

Henry obliged and waited for his master to arrive, but he never lowered his spear and maintained his surroundings—no matter how devoid of life they were.

Minutes later, Victor shot through the hole and surprisingly fit in the space without issues. He checked his status, and a new debuff appeared: (Fatal Mana Sickness[-100 stat points a second]). Silently cursing, he reached out a claw and carefully moved the mouse. The yellowy-tinted plastic mouse scraped across the surface, and a white arrow appeared—the screen brightened up as if it had been on power-saving mode.

Victor hovered over the only option presented to him, and with a silent prayer, he clicked Login, and a new popup appeared.