Four years later, on King Kai Planet...
The gorilla Bubbles lay sprawled on the grass, lazily scratching its armpit and dozing off when a faint, unnatural ripple in the air jolted it awake.
As an animal, Bubbles possessed instincts sharper than any human's. It scrambled up and soon spotted King Kai in front of the house—the stout deity standing with his arms raised toward the sky, his face scrunched in concentration behind his tiny round sunglasses. Whether his eyes were closed or not was anyone's guess.
The air, the ground, the grass, the flowers... everything, big or small, seemed to fall into an eerie stillness. Bubbles' ears twitched uneasily. Something was happening, but it couldn't tell what.
"Aha! I knew it!"
King Kai suddenly shouted, drenched in sweat but grinning triumphantly. "Just as we theorized! Only someone with a 'Heavenly Heart'—what a ridiculous name—can sense and channel the latent 'energy' hidden within all things by borrowing a trace of Heaven Ki!"
Over these four years of martial discussions with Yamiru, King Kai had drawn inspiration from Yamiru's experiments with Kinto-Un and, spurred by Yamiru's subtle hints, enthusiastically began developing a theoretical ultimate technique—
The very move that would one day become Goku's trump card: the Genki Dama (Spirit Bomb)!
At first, progress was impossible. They couldn't even take the first step.
Yamiru's claim—"Infinite energy lies dormant within all things, even the sun, the earth, and the air, waiting to be harnessed"—sounded grand, but how?
Close your eyes, and then what?
Where was this energy?
The air was just air. The earth was just earth. Where was this so-called "latent energy"?
Through trial and error, Yamiru proposed a key insight: to gather the Genki Dama, they needed a catalyst—a spark of Heaven Ki—and a "Heavenly Heart" capable of wielding it.
This was Yamiru's coined term, referring to the purity of spirit found in those worthy of ascending to Heaven.
Just as evil thoughts could attract demonic energy, a heart of goodness and purity could resonate with Heaven Ki.
Of course, just as not every wicked person on Earth could become a demon (only those with exceptional talent, like the genius Namekian who birthed Demon King Piccolo, could gather enough demonic energy to transform), not every righteous individual could summon Heaven Ki either.
It required aptitude.
For example: Goku could do it—hence his ability to learn the Genki Dama.
Piccolo, Tien, Yamcha, and Chiaotzu? Clearly not.
And now, King Kai stood in a gray area between can and cannot.
Borrowing a wisp of Heaven Ki, he had taken the first step—glimpsing the energy hidden within the air and earth.
But how to call upon that energy, to gather it willingly? That remained beyond his grasp.
Whether he could truly master it was still uncertain...
But as the technique's creator with infinite time to refine it, King Kai would likely succeed eventually.
For now, reaching this milestone filled him with confidence.
After basking in his achievement, King Kai suddenly scowled and snapped at the figure behind him: "Why are you still touching my back?! You've already learned it—you should be able to contact Earth on your own now!"
Behind him stood Yamiru, unchanged after four years, his hand resting on King Kai's back.
"Force of habit," Yamiru said, withdrawing his hand. Then, via telepathy, he reached across the boundary between life and death to speak with Annin atop the Korin Tower on Earth:
"...Yeah, I'll be back soon. Hah, a feast sounds great... Oh? Because you keep going down to gather hotpot ingredients, the climbers have started offering livestock sacrifices at the tower's base, praying for divine protection?"
"Yep," Annin replied dryly. "And none of them realize the god they're praying to isn't even on Earth."
"You're a god too," Yamiru pointed out. "They're praying to you."
"Acting god, at best."
"Don't pin their failures on me," Yamiru laughed. "If they can't climb up, that's not because I didn't bless them..."
Annin chuckled.
From his conversation with Annin, Yamiru learned that over the past four years, people from all over the world had continued attempting to climb the Korin Tower—sometimes dozens at a time.
Not a single one had succeeded.
The monkey-headed man who scaled the tower seven years ago remained the only successful challenger.
Now, after seven years of training under Annin, his journey was nearing its end.
"He's starting to sense ki," Annin said. "Though he's still clumsy with it."
Yamiru smirked. "You're just bored up there and deliberately not letting him grab the water pot, aren't you?"
"Hah! Caught me," Annin admitted.
Ending their cross-realm telepathy, Yamiru fell into thought before finally saying, "I should head back, Lord Kai."
"You still want to return?" King Kai blinked, scratching his head in confusion. "If you're dead, just go enjoy yourself in Heaven. Why avoid it?"
After four years together, the two had become close enough for blunt honesty. Yamiru sighed. "I'm afraid that if I fully embrace the Heavenly life... I'll drift too far from the living version of myself. Even now, with this thing—" He tapped his golden halo, his expression briefly bitter. "—I keep forgetting to eat or sleep. I'm losing basic desires. What happens if I forget her?"
"But you are dead," King Kai said, as if stating the obvious. "The dead should be different from the living. Why cling to both?" He shook his head. "Most souls in Heaven either accept their death and move on, or stubbornly keep living as they did before—eating, sleeping, pretending nothing's changed. But you? You're stuck in between. I've never seen that."
Yamiru's voice softened. "What if one day, I need to return to the living—to share a life with someone? If I change before then, if I sever that connection without even telling her... that would be unforgivable."
"Return to the living?" King Kai gaped. "You plan to reincarnate with your memories? King Yemma would never allow that!"
Yamiru only smiled.
"Race you—Flying Nimbus or Genki Dama. Who finishes first?"
"Dream on. My Spirit Bomb will win, easy."
With a final wave, Yamiru vanished from King Kai Planet.
The roar of Earth's winds and the bite of high-altitude cold rushed over him, whipping through his hair and filling his ears. When he opened his eyes, he glanced down.
Huh. Three bricks now.