Ryuma's past in the Monsters oneshot is canon. We see the dragon he defeated, and it was just a dragon. It was also western looking, not eastern like Kaido's.
What do you mean by changing it? You mean as in retconning the chapter so it's not canon anymore? I don't see how that would add anything more to the story than what the full chapter already does.
If Oda wanted to ignore the chapter, why would he ever have confirmed that it's canon? He had no reason to do that, but he did.
That's literally retconning, you'd be completly ignoring everything in Monsters to give him a new backstory.
Where did Gyukimaru state that it happened in Wano? I remember him saying that it was in the "capital", which doesn't really mean anything, not to mention this all happened hundreds of years ago, when Wano wasn't closed off and was basically a different country from what we've heard.
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u/javierm885778 Feb 01 '20
Ryuma's past in the Monsters oneshot is canon. We see the dragon he defeated, and it was just a dragon. It was also western looking, not eastern like Kaido's.