Strongest Existence Becomes Teacher-Chapter 179: Grom’s Invention

Dren strode down the metal hallway finishing his class, boots clanking against the rune-lit floor. His face twisted with irritation.

Dren slammed the door to his private laboratory shut.

His breath was uneven—half excitement, half spite.

"Tch... that old man, that bitch Mira, and that new bastard Zane whenever I think of them it makes me angry ..." he muttered while pacing. "Let’s see where they are now."

He crossed the dim workshop, filled with rusted cages, shattered runic plates, and a faint metallic smell of blood that never really left the room.

At the center sat a black globe, faintly pulsing with purple veins.

Dren placed his hand over it.

At once—

The world inside the sphere lit up.

His lips curled.

Through the globe, he saw exactly what Grom was seeing.

Thanks to the parasite.

Originally, only his superior—the one who granted him the Abyssal metal—could use this surveillance.

But last night, one of that superior’s subordinates came suddenly and "rewarded" Dren with shared access.

Now he could observe Everything Grom sees...

everything Grom say...

"How convenient," Dren whispered as his eyes sharpened.

"Let’s hear what the old fool is babbling about."

He leaned close, adjusting the runic dial to sharpen the audio.

Inside the sphere, Grom sat in his office across from Zane and Mira.

Their voices became clear.

"... Heart of the Deep Forge..."

Dren’s pupils shrank.

He sharpened his senses, letting the parasite’s connection enhance his hearing. Inside the globe, Grom’s voice echoed-deep, steady, explaining something important to Mira and Zane.

---

Inside Grom’s Office

Grom leaned back, exhaling slowly.

"What you sensed earlier, Zane," he said, "was one of my greatest creations.

The artifact I call—Heart of the Deep Forge."

Zane’s eyes narrowed with faint interest.

Mira’s widened with immediate excitement.

Dren’s widened too — for a different reason.

Grom continued.

"Years ago, I began researching the structure of our world—how mana forms, how the planet generates it."

He reached into a drawer and pulled out a small metal device — a palm-sized, hexagonal plate covered with thin runic grooves.

""I invented this device called the Vibrational Wave Emitter. A strange little device. It emits a unique type of vibration the paryicular thing about it that the waves pass through solids and gasses... but not through liquids."

Zane listened silently, eyes unreadable.

"I used the emitter to study the planet’s structure."

Grom raised a finger.

" My initial theory was simple — if the planet was entirely solid, the vibrations would pass cleanly through and back. But..."

"It didn’t and then you did the one of the greatest discovery ," Mira whispered.

"Yes," Grom said, eyes gleaming with old pride. "It stopped. Something inside blocked the signal. And after years of refinement, measurements, and testing... I found the answer."

Zane listened silently.

Mira held her breath.

"At the core of our planet is an enormous ocean of liquid mana. A mana-core too dense to remain solid and too volatile to form gas. Constantly swirling, generating infinite mana."

Mira gasped.

"Liquid mana... a planetary core...I read about your discovery.."

Grom continued, unaware he was being watched.

"Once I realized that... I spent years studying the phenomenon. And eventually— I had a revelation."

"That discovery inspired me. ."

He placed a hand over his chest.

"I decided to replicate the planet’s process. To create an artifact that could produce mana endlessly."

Mira blinked rapidly. "A... device that generates infinite mana...?"

Yes but in the end...."

"And you failed?" she asked softly, almost fearing the answer.

"I succeeded."

Mira’s breath stopped.

Zane’s eyes narrowed.

And Dren—watching through the globe—felt a cold thrill crawl up.

"The result of decades of research.

An artificial core.

A miniature heart of mana."

His voice deepened.

"The Heart of the Deep Forge."

Dren’s fingers trembled around the viewing globe.

And he leaned closer to the sphere, listening harder than ever.

Mira’s brows knit together, confusion and hurt overlapping.

"Master Grom... how come I never heard about this? You never mentioned anything like this when you taught me. If you created something so groundbreaking, something that could change the world... then people should’ve known. I would’ve definitely heard about an artifact capable of generating infinite mana."

Grom exhaled deeply, shoulders sinking as if a weight he kept buried for years finally resurfaced.

"That," he said slowly, "is the part I was about to reach."

Mira leaned closer.

Grom continued, voice heavy:

"When I completed the prototype—using the finest material I had ever crafted, Truestone Alloy—I believed I had succeeded flawlessly."

His hands curled into fists.

"But my calculations... went off."

Zane’s quiet voice cut in.

"The material couldn’t handle it." 𝗳𝚛𝚎𝚎𝘄𝕖𝕓𝕟𝕠𝚟𝚎𝕝.𝗰𝕠𝐦

Grom nodded sharply.

"Exactly. Even Truestone Alloy couldn’t bear the pressure of infinite mana generation. The structure began destabilizing almost immediately. The thing that was supposed to be the world’s greatest invention quickly became... a disaster waiting to happen."

Mira’s face paled. "Unstable mana... inside an artifact?"

Grom let out a bitter laugh.

"Once perfect. Now an unpredictable, volatile core. A ticking calamity."

"The Heart of the Deep Forge," Zane murmured. "That’s why it’s sealed."

"Correct," Grom said. "I had no choice but to seal it deep underground, in a reinforced chamber. Hidden from everyone. Not because I wanted to keep it secret... but because revealing it would put the entire kingdom in danger."

Mira whispered, "Why didn’t you destroy it then...?"

Grom turned toward her—expression grim.

"Think, Mira. If I could destroy it safely... I would have."

He let the weight of his words sink in.

"But an unstable infinite mana core doesn’t simply vanish when broken."

His gaze shifted to the floor, voice dropping.

"If I tried to destroy it outright, the resulting mana detonation wouldn’t just wipe out the academy..."

He took a breath.

"It could annihilate the entire Gravundar Kingdom. Possibly more."

Silence fell.

The air felt heavier—almost suffocating.

Grom exhaled slowly, leaning back in his chair as though the memories weighed on his bones.

"And as for you, Mira... the reason you never heard about any of this is simple."

His eyes softened.

"I sealed the Heart of the Deep Forge before you ever became my student. Before you stepped foot in this academy."

Mira froze.

"But... then... does Dren know about it?"

Zane’s eyelids lowered slightly, a faint smile curling at his lips.

Ah... here it comes.

Grom hesitated.

A shadow crossed his expression—regret, guilt, something darker.

"...Yes," he admitted. "He does."

Mira’s eyes widened in shock.

Grom continued, voice low:

"I hid it from him at first. I truly did. But Dren... that boy always had a sharp mind. Too sharp. He eventually discovered traces of my experiment, followed the clues, and confronted me."

His fists tightened.

"He wanted to help. Wanted to ’perfect’ it. Said that together, we could find a way to stabilize the core... that it would bring glory to Gravundar."

Mira held her breath.

"But I refused," Grom said firmly. "I knew the risks. I knew one mistake could doom the entire kingdom. So I reinforced the seals even further and forbade him from ever touching it again."

Zane watched quietly, eyes half-lidded.

And after that... you thought he "understood," didn’t you?

Grom gave a weary sigh.

"At the time... I believed he accepted my decision. He stopped asking questions. He returned to his studies. He even apologized."

Mira whispered, "So... he let it go?"

Grom nodded slowly.

For a moment, the room fell quiet.

Zane leaned back slightly, eyes half-closed, a faint smirk tugging at the edge of his lips.

I know a way to make this even more interesting...

Much more interesting.