After returning to King Kai's Planet, Goku found that everyone had passed King Kai's "make me laugh" test.
Training officially began.
Monkey Trials
"The first step," King Kai announced, "is to overcome this planet's gravity and catch Bubbles.
If you can't even do that, forget everything else."
Everyone nodded.
"Understood!"
The chase began.
King Kai sipped his tea, relaxing—until someone rushed in with a report.
"All of them caught Bubbles."
"...What?"
He stared blankly at the little monkey.
Bubbles gave a pitiful nod.
King Kai sweatdropped.
"You guys couldn't even move a few days ago. How the hell did you adapt so fast?"
Chi-Chi wiped sweat from her forehead.
"The gravity here's 10x Earth's, right? We've been training for that already."
She held up her wrist.
"These gravity wristbands were designed by Bulma.
We've been training under 10x gravity back on Earth.
With the bands turned off, this is child's play."
King Kai squinted at the devices, then sucked in a breath.
"Incredible… external gravity regulators."
Krillin scratched the back of his head.
"King Kai, can we start learning martial arts now?"
King Kai sighed, then grinned.
"Alright, but my training is much tougher than Kami's! Are you ready?"
All six shouted in unison.
"Ready!"
King Kai's smile widened.
"Good. Now remember, once you accept my training, there's no backtalk. Do as I say."
"Yes, sir!"
He inhaled deeply.
"True martial arts—of the body and the spirit—require time.
Rushing leads to failure.
You're all already adapting to 10x gravity. That means… there's room for more."
He gestured toward Bubbles.
"Crank up those gravity bands and keep chasing Bubbles.
Push until your bodies hit their absolute limit.
Only then will I teach you anything else."
The group looked at one another.
So far, King Kai's training… was a more annoying version of Master Roshi's milk delivery.
King Kai saw their expressions.
"What? Didn't you just promise to follow orders without complaint?"
"Yes!" they barked.
"Great. Now get to it!"
He strolled back inside to enjoy his tea.
Ascending Gravity
Everyone adjusted their bands to their limits and resumed monkey-chasing.
Goku pushed his band to 3x, and with King Kai's gravity, he was now training under 30x gravity.
It felt like running with a sack of concrete on his back.
Krillin and Chi-Chi weren't far behind.
Tien, Yamcha, and Chiaotzu lagged a bit but trained hard to catch up.
Time passed quickly.
When King Kai learned some had already adapted to 50x gravity, he was quietly shocked.
"These are mortals… and they've surpassed me."
He knew it was thanks to:
Master Roshi's foundational trainingBulma's techGuidance from Korin and Mr. Popo
Their only real flaw was that everything had gone a little too smoothly.
No bottlenecks. No real enemies.
Some were starting to lose motivation.
Still, the results were undeniable.
After a year:
Goku adapted to 100x gravityChi-Chi and Krillin: ~80xTien: 80x, by sheer willYamcha and Chiaotzu: ~50x
King Kai finally announced the next phase.
Kaioken and Spirit Bomb
"It's time I teach you my secret techniques:
Kaioken and the Spirit Bomb."
Everyone leaned in.
"But let me warn you," King Kai added, "Kaioken is still experimental.
It's powerful—but dangerous.
Misuse it, and it'll wreck your body.
Even I haven't mastered it yet."
Goku's eyes narrowed.
'So that's why Kaioken damages the body—it's not complete?'
Seeing their doubt, King Kai cleared his throat.
"What? You don't want to learn?"
"Not at all!" Goku smiled.
King Kai nodded.
"Kaioken requires extreme physical resilience.
The stronger your body, the more times you can multiply your power.
If your body can't handle the strain, it'll collapse."
The group now understood.
This past year hadn't been stalling—it was the groundwork.
"Understood!" they echoed.
King Kai's antenna twitched in amusement.
"Excellent. Then let the real training begin!"
Mastery Timeline
After 1 month, Goku mastered Kaioken.1.5 months, Tien followed.2 months, Krillin succeeded.3 months, Chi-Chi.6 months, Yamcha.1 year, Chiaotzu gave up.
Goku eventually maxed out gravity adaptation and wore weighted armor, bringing him to 200x gravity.
In the end:
Everyone except Chiaotzu adapted to 100xYamcha finally caught up
Two Years Later
King Kai gathered them.
"It's been two years.
You've all surpassed me.
You've learned Kaioken and the Spirit Bomb.
There's no more I can teach you here. It's time to go home."
Everyone was stunned.
"Two years already?"
"It feels like yesterday…"
Krillin let out a long sigh.
"Finally.
If we weren't training together, I would've lost my mind."
Chi-Chi smirked.
"You just miss Snow, don't you?"
Everyone burst into laughter.
"Hahahaha!"
Krillin scowled.
"Mock me all you want, but at least I'm not single!"
Yamcha, Tien, and Chiaotzu fell silent.
Tien and Chiaotzu didn't care.
Yamcha… looked genuinely distressed.
Goku and Chi-Chi ignored it entirely.
They weren't "single."
They were childhood sweethearts—inseparable since forever.
Chi-Chi beamed.
"We're finally going home! Aren't you happy, Goku?"
Goku nodded.
"Yeah. Training here's been amazing, but there's nothing to do besides training."
"Then let's ask Bulma to take us out somewhere to relax!"
"Sounds good."
"But Goku—back on Earth, be careful with your strength, okay?
No showing off."
"I know."
Everyone understood.
After all, with this much power, even a casual bump could be lethal to a normal person.
So, precise Ki control became part of daily life.
They trained themselves to suppress energy, limit output, and minimize fatigue.
With farewells to King Kai complete, the group eagerly returned to Earth.
West City – Bulma's Private Estate
A thousand kilometers west of the city, near the sea, sat a luxury villa.
Though it had dozens of chefs and staff, there wasn't a single guest.
Because it belonged to Bulma.
That afternoon, Bulma lounged under a parasol in a swimsuit, sipping tea.
Behind her stood a towering building—the Gravity Training Facility she'd built for Goku.
Massive. Bigger than a concert venue.
Outfitted with machines, refreshment stations, and more.
But no one had used it. Not even once.
She adjusted her sunglasses and sighed.
"Two years…
That idiot still hasn't come back."
She thought of Goku's face—that charmingly clueless grin.
And smiled.
Just then, a voice cut through the breeze.
"Bulma! I'm home!"
Bulma froze.
She yanked off her sunglasses and shot to her feet.
There he was—Goku, standing before her in his orange Turtle School gi.
His face hadn't changed much, but something about his eyes was different.
Clearer. Sharper. Wiser.
Without thinking, Bulma ran up and threw herself into his arms.
"You jerk! Two years! Not even a single visit!"
She pounded his chest with tiny fists, eyes brimming with tears.
Goku gently caught her wrists.
Bulma froze.
He'd never stopped her before.
She tried to pull away—but his grip was firm as steel.
She raised another hand—only for Goku to grab it too.
Then he pushed her gently against the villa wall.
"I missed you, Bulma."
She blinked.
The next instant, he kissed her—hard.
Bulma's eyes widened, breath stolen.
Then slowly, her arms wrapped around him, lips answering back.
Her legs trembled.
Her nails bit into his back.
It had been a long, long wait.
And now—he was finally home.