A few minutes later, Saitama stepped out in his yellow jumpsuit, looking refreshed.
"Let's go!"
Genos extended his mechanical arm.
"Please grab on. I'll take you both down."
Kaito and Saitama each took hold of one of Genos's arms. The cyborg lifted them, rising slowly before plunging straight down into the deep pit.
As they descended, the light faded and the air grew colder. Genos deployed a high-powered flashlight from his arm, its beam cutting across damp rock walls.
"This pit's deeper than I thought," Saitama's voice echoed in the darkness.
After nearly ten minutes, they touched down at the bottom. The light revealed a dim tunnel, three meters high and wide enough for five people to walk side by side. Claw marks gouged the stone, and glistening slime clung to the walls. The air stank of rot.
"It seems we've found the Monster Association's lair," Kaito murmured. His Emperor Engine began to rumble involuntarily—low, steady, "thump… thump…"
Saitama cracked his knuckles with a "crunch-crunch."
"Perfect. Time to stretch my muscles."
They advanced, Genos in the lead, his light sweeping across each branching path. The tunnel system twisted like a massive labyrinth.
Now and then, low-level Monster Association members stumbled into their path—unlucky enough to meet Saitama's fist or freeze in terror at the ominous roar of Kaito's Emperor Engine. With every fallen foe, deterrence points poured in like an endless stream.
Meanwhile, deep in the Monster Association's core, the walls glittered with embedded fluorite stones casting a sickly green glow. The light painted the vast cavern in a hellish hue.
Upon a throne of bones and flesh sat a colossal figure—over a hundred zhang tall—its body woven from countless monstrous pythons. Each snake's gaping maw flicked a crimson tongue, the air thick with a stomach-turning stench.
This was Orochi, the fearsome leader of the Monster Association.
Before him floated a pulsing pink mass, its wrinkled surface veined in red, with one enormous, unblinking eye.
This was the true mastermind—the strategist known as Great Eyes.
"Hehehehe…"
Through the network of its "Little Jiongyan" avatars scattered throughout the tunnels, Great Eyes had been watching Kaito's group.
"Heaven truly favors me," it rasped, its voice like nails on glass. "I wondered how I might collect combat data on the Hero Association's most mysterious King… and here he is, delivered to my doorstep."
Its single eye gleamed as it swept across the gathered executives.
"Who will deal with King?"
Two figures stepped forward immediately.
"Let me!" snarled a bug-type monster encased in a hard carapace, three eyes glowing with malice. "I, Insect God, have long craved King's fresh blood!"
"And me!" said another, hefting two serrated greatswords before licking one blade. "I, Cutting King, love slicing heroes into pieces."
These two Demon-level executives were infamous partners, rarely acting alone.
"Very good," Great Eyes said, then turned toward a shadowed corner.
"Awakened Cockroach—go as well."
The humanoid insect rose from its crouch, its human-like torso covered in glossy black shell. Six spindly limbs extended from its back, antennae twitching constantly.
"As you command."
The three vanished into the tunnels.
"Hmph!"
The voice was sharp and annoyed. A figure made of countless black cells stepped out—Black Sperm, a Dragon-level executive.
"Why not send us Dragon-level fighters? I want a shot at King too!"
Great Eyes swiveled its massive eye toward him.
"I have my own arrangements."
Its gaze drifted deeper into the cavern, where terrifying silhouettes waited—Gums, Homeless Emperor, Rover, Ugly President… each capable of leveling a city.
"King's strength is unknown," Great Eyes said with a dark chuckle. "Let the Demon-levels test his limits first…"
Somewhere in the maze of tunnels, Kaito froze. His Emperor Engine roared to life, pounding violently.
Thump-thump! Thump-thump!
The heartbeat reverberated in the stone walls, dark red aura flaring around him like fire.
"What's up?" Saitama asked, glancing back.
"Something's coming," Kaito said, his eyes narrowing to razor points. "Three… and they're no pushovers."
Genos's arms unfolded, his energy core charging.
"Teacher, Mr. King, please step ba—"
He never finished.
BOOM!!!
A black blur ripped through the air, leaving afterimages in its wake. The air screamed with the sound of its movement, the stench hitting them a second later.
It was Awakened Cockroach.
."
It struck in the instant Genos opened his mouth—exploiting the split-second distraction—its speed surpassing the limits of human sight. The blow slammed into Genos's alloy chest.
Thud—!!!
The impact was dull, deep, and gut-punching. The two of them were sent hurtling through the tunnel, smashing through three layers of rock before vanishing into the depths.
"Genos!" Saitama shouted into the dust-choked hole. "Need a hand?"
From somewhere ahead came the clang of metal and the high-pitched whine of an overloaded energy core.
"Please don't worry, Teacher… I'll handle this cockroach!"
Genos was clearly furious. The ambush had lit a fire under him—he wasn't about to let this insect slip away.
From the gaping breach in the rock, two more shapes emerged.
Insect God. Cutting King.
"Hehehehe… lucky day," Insect God hissed, his three crimson compound eyes scanning Kaito with hungry fixation. "The legendary 'Strongest Man on Earth,' King… your head will be the crown jewel of my collection!"
Cutting King licked the serrated edge of his blade, its steel streaked with a dark, unknown residue. He jabbed the point toward Saitama.
"That bald guy's mine! Looks like perfect sashimi material! Hey, cue ball—you ready to get minced? Hahaha!"
Their arrogance was absolute. Their contempt, palpable.
Kaito almost laughed. How long had it been since he'd run into such pure, undiluted idiots?
He rolled his neck, joints cracking like snapping beans. Dark red aura flared around his feet.
"Saitama," he said evenly, "hit slower."
"Oh?" Saitama stopped picking at his ear, eyes lighting up. "You wanna play that game?"
It was a little pastime Kaito had suggested earlier, when they'd been swatting small-fry monsters—drawing out the fight to make enemies feel true, bone-deep fear before finishing them off. A fitting tax for the havoc they'd caused in the human world.
Kaito didn't answer. He simply stepped toward Insect God.
With each step, the Emperor Engine's roar grew louder. Dust trickled from the tunnel walls.
Information from the Hero Association database flashed through his mind:
Insect God — Demon-level peak.
Carapace defense known as Iron Wall, able to channel that durability into devastating kinetic counterattacks.
Even more dangerous—he could transform into a Six-Arm Form, quadrupling both speed and strength. A heavy-tank type combatant. Maximum defense as maximum offense.