Kaioken and the Spirit Bomb.
In Dragon Ball, any mention of King Kai inevitably brought these two techniques to mind.
Before Son Goku gained the ability to transform into a Super Saiyan, Kaioken had always been the technique that let him turn the tables and challenge opponents stronger than himself.
The Spirit Bomb, meanwhile, remained Goku's ultimate trump card for defeating powerful enemies right up to the end of the story.
With this rare opportunity to visit King Kai's Planet, Lin Chen's main goal was to learn those two techniques.
Several of Lin Chen's previous choice missions had offered Kaioken as a reward, but he had passed them up. This time, he would not miss it again.
"You want to learn my techniques?"
"That's right. I heard that you've spent years observing martial arts in the lower realm, King Kai, and devoted your life's work to developing several techniques. I'm very interested in them. Would you be willing to teach me?"
North Kai considered it for a moment, then said, "You're pretty well informed, aren't you? To be honest, since you got rid of that fiend Frieza for me, I have no problem teaching you my special techniques."
"All right, you just have to tell me a joke that makes me laugh. But let me warn you first: it's very hard to make me laugh. Ordinary jokes don't work on me at all."
Lin Chen had known this was coming. "That's easy. Listen closely."
"Three little rabbits were pooping. The first one's poop was long, the second one's was round, and the third one's was actually triangular. When they asked the third rabbit about it, he answered, 'I shaped it with my hands.'"
"Sh-shaped it with his hands!"
North Kai's face froze. Then he clutched his stomach and burst into