Following the fight against the Strix, Isshin was rewarded with a large number of cultivation gems.
He wasted no time.
The instant he was back in his chambers, he sat down and started taking in the Qi around him, utilizing all his concentration to firm up his core.
Thunder crackled within his veins. His energy churned, becoming denser, heavier.
After a full round of cultivation, Isshin's basis shook — and steadied.
He had finally reached the 7th step of the Golden Core Realm.
And despite his breakthrough, Isshin wasn't satisfied.
Sheer strength would not be enough to survive here.
He retreated into his inner life, where Raijin had been expecting him
This time, Raijin had a new technique to teach him.
"The next battle won't be won by power or speed. You'll need creativity. Let's begin."
The operation was named Thundercrack Burial.
It involved plunging his sword into the ground, concentrating Thunder Qi deep into the earth — causing a furious eruption that shattered the ground.
But that did not end it.
The real genius of the strategy was what followed after the explosion:
the rocks that had been blasted into the air would then become Isshin's arsenal, and he would have to Flash Step around and kick the rocks at his enemy at eye-blinding speeds, turning the environment itself into a hail of deadly projectiles.
Early on, Isshin struggled.
His timing was wrong — he would either kick the rocks too late, or his kicks would propel them too slowly.
The coordination it needed was something he had never trained for.
But the time dilation of the inner world was his strongest weapon.
Where hours passed on the outside, Isshin trained for months on the inside, practicing the Thundercrack Burial until the sequence became second nature.
He failed.
He fell.
He stood up.
And slowly, he mastered it.
Time went quickly in the real world.
Before long, two weeks had elapsed.
The onlookers were interested.
Isshin was hardly seen between matches, locking himself away in his chambers at all hours. Rumors began to spread — some believed he was hurt, others that he was practicing some outlawed method.
No one knew the truth: in that silent, small room, Isshin was transforming into something far more deadly.
And the day of the third battle arrived.
Isshin came back into the arena, thunder echoing gently in his core.
His opponent was already waiting — a giant soldier in heavy, black armor holding a massive greatsword nearly as large as himself.
There were no words spoken.
No greetings.
Battle only.
The moment the horn was blown, the soldier attacked like a wild beast.
The ground shook under his ponderous steps.
He lifted his huge sword above him and brought it down with a frightening impact.
BOOM!
Isshin sidestepped quickly to the side, narrowly missing a straight hit — but the shock of the collision shook his bones and left him stumbling off balance.
Before he had a chance to recover, the soldier swung sideways, targeting Isshin's head.
Isshin crouched low, his knees grazing the earth, sensing the fatal arc of the sword cleaving the air overhead.
Too fast. Too strong.
This opponent was no mindless brute.
Isshin used Flash Step, backing away but at the same time shooting Thunder Qi Arrows from the tips of his fingers.
Scorching bolts of lightning flashed across the battlefield, compelling the soldier to defend.
Yet Isshin required more.
It was time to implement the new technique.
Planting his sword in the ground, he directed a burst of Thunder Qi into the earth.
The earth beneath the soldier erupted — a thunderous explosion propelling massive rocks of stone high into the air.
The soldier roared and swung indiscriminately, slashing through several of the incoming boulders with brute force.
But he couldn't stop all of them.
He was hit on the side by a stone and stumbled.
Before he could orient himself, a second — and a third — hit him in quick succession.
The huge soldier was swept from his feet, slamming onto the ground with a deafening crash.
The stadium fell silent for a while.
Yet the soldier was not done.
He snarled furiously, forcing himself upwards, his armor battered, his hand clenched on his greatsword.
He charged once more, quicker and more desperately than before.
Isshin sidestepped, barely missing the berserker blows.
He knew he needed to disarm him somehow.
Without that enormous sword, the threat from the soldier would be much diminished.
A thought occurred to Isshin.
He replayed Thundercrack Burial, causing a second eruption.
As the soldier focused on slashing through the flying debris, Isshin took his opportunity — closing the distance in an instant.
The soldier cut through the final rock — only to discover Isshin already upon him.
Isshin's sword glowed with terrible might as he struck:
Sword of Raijin: One Slash.
A single, precise, devastating strike. SHHRRRK! The armor of the soldier tore, a wide slash across his chest. He staggered backward, his greatsword falling from his hand — and then, like all the others before him, vanished into mist. The arena burst into applause. The crowd chanted and shouted Isshin's victory, cheering his name. Far overhead, the Skeleton King sat motionless, his bony fingers drumming a rhythm on his throne. There was, for the first time, a flicker of irritation in the King's empty stare. Silently, a new reward was thrown in Isshin's direction. Isshin caught it calmly. Victory again. And two weeks later, the fourth battle awaited him.