When Dragon Ball fans think of Goku's training scene, King Kai's planet or the Hyperbolic Time Chamber likely stand out in their minds. Or, if they're limited to the original series, they associate it with Master Roshi's chore list for Goku and Krillin. In truth, the best moment is in chapters 87 to 90 of the original Dragon Ball manga by after Goku loses against the assassin Taopaipai, who mistakenly believes he killed the young Saiyan and leaves.
Upon realizing that he left one of the Dragon Balls that the Red Ribbon Army hired him to obtain from Goku, Taopaipai decides he'll retrieve it after getting a new outfit tailored for him, since Goku seemingly wasn't going anywhere. Meanwhile, Goku takes advantage of Taopaipai's absence by trying to drink Korin's Holy Water to get stronger, but discovers that the Holy Water isn't special. Korin instead increases Goku's strength by making him climb up his tower to try and take the Holy Water from him.
Korin's Training Isn't a Rip-Off
This situation is effective for two reasons. Goku is lucky to have gotten the chance to train – had Taopaipai not wasted time getting his outfit tailored, the assassin would have realized he hadn't defeated Goku, making it impossible for Goku to recover. Additionally, Goku's training with Korin is a more compelling variation of Master Roshi's sessions with Goku and Krillin. Roshi's training involves Goku and Krillin participating in more extreme versions of mundane, everyday tasks, reminiscent of Mr. Miyagi's "wax on, wax off" technique in Karate Kid. Korin's regimen is presented as more of a challenge to overcome instead of deceptively worthless chores.
Dragon Ball Z and Dragon Ball Super copy these points, but fail to improve upon them. DBZ replaces how Goku has to exert himself more because of thin the air is at the top of Korin's Tower. Comparatively, King Kai's tasks with Bubbles the Monkey and Gregory the Cricket are just more absurd versions of Master Roshi's tasks. King Kai never misdirects Goku like Korin, either. The Hyperbolic Time Chamber just takes out the compelling nature of misdirection and relies completely on time warps to justify massive increases in strength.
Moro Has Nothing On Taopaipai
There are even fewer examples of villains doing what Taopaipai does for Goku. The best example is during Dragon Ball Super's Galactic Patrol Prisoner Saga, when Moro allows Goku and Vegeta to train, resulting in them generating more energy for him to later absorb. Both Taopaipai and Moro suffer from their own arrogance. The difference is that the stakes are much lower in Dragon Ball Super since Moro refuses to interfere with their training – even if it's at his own detriment. It's only when Moro attacks Earth that the circumstances change, but even then, readers want Goku and Vegeta to stay away, so Earth's other heroes get a chance to fight.
In Dragon Ball, Taopaipai has no idea that Goku is training and would have undoubtedly stopped him had he known. And instead of being doubly careful, he decides to adhere to his own ridiculous standards, which also has a suspenseful thee-day time limit. Meanwhile, every other villain in the franchise either can't reach Goku when he's training, or is unaware he's training but not due to a personal shortcoming. Like what happens with the introduction of Super Saiyan and the Kaio-ken, DBZ and Dragon Ball Super feel lazy by comparison.
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