Personally, I'm not sure what else could be done with Kaido's past besides infodumping lore. We've seen him at ten years old, which is about as young as you could expect anything lifechanging to happen. We've learned his personal worldview - that of a young man too strong to bow to authority, aware of the unfairness of the world's power structure and angry enough to want to tear it down, but not righteous enough to want to build anything more equitable in its place. A nihilist with the raw power to back up his philosophy.
You say it was all lore, no motivation, well I see it the exact opposite way. He didn't grow up in an important for the future, isolated from the WG nation like Big Mom did on Elbaf, he just came from a normal human kingdom struggling to make ends meet under World Government taxes, and we see how that's coloured his perception of the world. The backstory we're shown, the use as a pawn, the time spent on the run, the reinforcement of might making right, it all feels like it leads right to the man we see today.
Everything that's left to know would involve explaining other things he connects to. Ancient races like the oni and lunarians, the reason the World Government sees Nika/Joyboy as such a threat to their established order (easy to see why Kaido would get obsessed with that after what we've just learned about his mindset), and what kind of man Rocks was and what he taught the pirates he sailed with. But none of those are exclusively Kaido's plot points. Maybe we'll get bits and pieces of them during the epilogue, maybe all of one of, maybe none. They're all things we'll learn about eventually, but they could be saved for later.
I don't really have time today for the hourlong video you've linked, but personally, I think our current understanding of Kaido is solid enough to move on from. There's maybe a loose end or another scene to show in how he went from Joyboy being simply the person to beat him to a desire to actually get killed in the process, but I could definitely just chalk that up to an already angry and extreme personality getting more frustrated and pushing his ideas further to the limits as he ages.
Also, Alabasta gave us narration designated winners for all the crew fights except Luffy's. Even in Onigashima, it's only Zoro, Sanji, Raizo and Kid and Law who got the narration treatment. The Tobi Roppo got a "defeated" narration as a group, long after they were all felled without designating the winners (nothing at all in their individual chapters), as did Perospero and Jack. That's all not to say Luffy couldn't get a winner narration, but it's so inconsistent even just limiting our scope to Onigashima that I wouldn't dream of calling it a requirement.
My eyes say the ground. I can almost get spoiler providers getting the landing site wrong from low quality pictures or just hastily typed summaries, but the wiki one is 100% someone not looking hard enoguh at the art and still assuming they understood everything at a glance. I wouldn't rely too much on the wiki, it has a lot of that kind of thing.
To be clear, I love the flashback we got - and it was packed with a lot of really interesting details. But what I mean to say is, it's not done in the same style as Oda's flashbacks which are more typically like something out of Lost (minus the cutting back and forth between the past and present part). They don't just show us things that happened to a character, but a dynamic event in their past which shapes their present goals or worldview. They don't just explain what happened to a character in the past. They answer the 'why' question. Why does Big Mom want to create a utopian candyland? Why does she want to make everyone giants? Her backstory shows us the trauma which birthed the monster. Which represents a growing trend in the New World. Doflamingo received the same treatment.
And this is important - because the Straw Hats are no longer merely fighting evil despotic pirates. They're fighting entrenched systems of abuse and hatred which continuously produce villains in the same mold like Hody Jones, Orochi, Kanjuro. These Emperors in particular represent dark inversions of JoyBoy. Their visions for the world transformed are twisted reflections of that which JoyBoy was trying to accomplish. They're shadows of the hero, moved by the same forces as Luffy (dreams, fate, inherited will), and seek the same goal (One Piece), but the distinction is the type of world they're trying to create.
What's most interesting about Kaido's flashback is what it doesn't tell us. It doesn't tell us 'why is Kaido?' Kaido was a static force throughout the flashback. At every phase of his life, from the age of 10 to the age of 59, he has been pursuing the same goal. But why? Who instilled these values in Kaido? A common facet of New World villains is an inversion of the mentor-mentee relationship. People like Arlong corrupted Hody. Trebol corrupted Doflamingo… or at least made him worse. Higarushi corrutped Orochi and Orochi in turn corrupted Kanjuro.
By age 10, Kaido was already a child mercenary fighting for the Vodka Kingdom. A lone Ogre surrounded by humans. At no point in this battle did Kaido express anywhere near the same level of heated emotion as he did in his battle against Yamato in chapter 1025. "Ogres aren't meant to be friends with humans!" His face was twisted into an evil, demonic form as he he bellowed these words to his daughter - because they represent the deep trauma which birthed the monster.
That's what we didn't get in this flasbhack - and I believe that's still coming.
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I would disagree on that. I was going to make a list of the threads the fb tied together but then someone went and totally did exactly that in the sp thread.
The fb was spot on on laden with all sorts of aspects/mysteries we've been presented with over the years.
I really enjoyed that.
The significance of the matsuri being uninterrupted.
And Luffy's words.
The drama is all there.
But Oda failed to tie the drama and action together like he almost always does.
It actually felt like reading another series.
In my above response to Captain M, I think the reason it didn't connect, as you said is because there is this fundamental disconnect with Kaido.
The dramatic tension in Luffy and Kaido's battle derives entirely from the JoyBoy lore. Which, yes, is tied to Wano. We know Luffy is fighting to open the borders. But we don't know why it's so important for Kaido to hold this particular country. Why this place? What makes it so special?
Kaido's dialogue to Luffy is dispassionate. Almost analytic. Analyzing whether or not Luffy's fit to be JoyBoy. Compare to his battle in chapter 1025 against Yamato - which was far more emotionally charged. That's the type of passion I would have expected to see in the final clash between Luffy and Kaido. Because it's not just about who's stronger. They're putting their dreams on the line, but Kaido only let his real emotions bubble to the surface while he was under the influence and when he fought against Yamato.
That's why I don't think it's quite over yet.
I also noticed in the spoiler thread you discussed the issue of Luffy overpowering the 'world's strongest creature.' And I share your concern.
But I'd like to hear your thoughts about the following. This is a summary of a theory video I have posted several times over the past couple years:
Kaido’s Devil Fruit is based on an Eastern Style Dragon and thus imbues him with incredibly good fortune in combat, based on associated real-world mythology and folklore. This ‘good fortune’ factor kicks in specifically when facing an opponent one-on-one. Kaido is undoubtedly monstrously powerful – I’m not suggesting any artifice in the way he has been presented thus far, but when the chips are down and Kaido faces a truly worthy opponent, the odds are always, overwhelmingly in Kaido’s favor. Thus, defeating Kaido means not only overpowering him, but overcoming these seemingly insurmountable odds. If, as I have suggested, this factor kicks in specifically in ‘one-on-one’ fights, Luffy may very well require the assistance of the ‘Nine Shadows’ from Toki’s prophecy to stand by his side in order to triumph of the world’s so-called ‘strongest creature alive.’
Kaido’s entrance into the narrative was accompanied by a narration box which reads, “In a one-on-one fight, always bet on Kaido.” The choice of the word bet is revealing and the qualifier ‘one-on-one’ has significant implications for the manner in which Kaido’s winning streak will finally come to an end.
The narrator plainly stated Whitebeard was the world’s strongest. The narrator says people in the One Piece world believe Kaido is the strongest. The former is definitive, the latter is speculative.
Oda has consistently used gambling motifs throughout the entire story saga, which began on Dressrosa. Kaido’s commanders, the Tobi Roppo, Calamities, and Numbers (as well as the subsidiary Donquixote Family) have names themed after card games – or, in other words, games of chance.
In chapter 1,012, Yamato lingered on the phrase ‘one-on-one,’ echoing the words of the omniscient narrator from Kaido’s introduction. Kaido has been defeated 7 times, but never ‘one-on-one.’
Pure dumb luck, in the form of uninvited outside intervention, intervened to save Kaido, not once, but twice when he finally faced a worthy opponent – against Kozuki Oden in chapter 970 and Luffy in chapter 1042.
I really want to zero in on the point about the narrator. The language shift is very subtle, but important. Note that as Kaido’s introductory scene opens, the narrator describes the manner in which Kaido has been defeated, captured, and pursued death as fact. There is a subtle but deliberate shift at the end of the passage with the narrator no longer directly stating known truths about Kaido, but instead telling readers about the way other characters perceive Kaido. Placing this description alongside a demonstration of Kaido’s incredible durability leads readers to believe Kaido lives up to his reputation as the world’s strongest creature. This is a clever narrative trick on Oda’s part to draw reader’s attention away from the fact that the narrator declines to comment on whether or not this particular statement about Kaido is true.
There's a lot more to this theory which I think makes it more compelling - like chapter 795 opens on Fujitora casting dice to decide Luffy's fate and ends with Kaido's introduction. The Beast Pirates and Donquixote Family have names themed after games of chance, etc.
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I can honestly say having read every 'major' fight weekly since Water Seven, this is the first time I have had this feeling that I can best describe as just - incomplete. I'm not saying 'I don't like it'. It just feels like there's something missing still. Like we're still waiting for a crucial piece to fall into place. And personally, I believe it's centered on two factors - the importance of Kaido's Devil Fruit, and the roots of his motivation which bring forth his true, genuine emotions. For every other major villain - it's all on the line in the final clash. Not just in terms of strength, but their dreams. Luffy defeating Kaido alone while Kaido is also entirely focused on Luffy's desires / dreams rather than his own seems almost... perfunctory. Luffy won because that's what heroes do. And he'll get as many powerups, miraculously resurrect as many times and make his fist as big as needed to make that happen. And Kaido just falls when he's supposed to. Like actors in a kabuki play.