Greg gave an interview to the German One Piece community, just stumbled over it on Reddit:
! How do Oda and his team react to spoilers / leaked chapters before the official release on Manga Plus?
I don't have his personal thoughts on them so I won't put words in his mouth or speak for him. I do know the stance of his editors and their opinion of them is not one I'm comfortable repeating in public verbatim without their permission. I'll just say that if anyone loves the series and wants any hope of meeting Oda by means of a working relationship, you won't even get your foot in the door if you deal in spoilers. Because DMCAs aren't being sent out left and right doesn't mean they don't recognize what's going on, or who is responsible.
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! Donquixote Rocinante "Corazon was a spy for Sengoku. Was he a member of the SWORD unit?
He may have been. I'd like to think that what happened to him sparked the creation of the SWORD unit in order to protect future Marines in a similar scenario.
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! Does Oda hint something in Color Spreads? Like, was the death of Portgas D. Ace foreshadowed in some?
Interesting question! I think you're talking about the one where they're playing cards, yeah? I can't say for certain one way or the other because I don't know about that in particular….BUT! I can give you a concrete example of one that's debatable. In the FILM Z spread with all the Marines, Corazon's face is hidden behind (if I recall correctly) behind Nami's tact. This was far in advance before he appeared in the story and also informs us that (at least in somewhat extended lore) Corazon was a student of Zephyr. So, yes, it's a possibility!
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! The book of devil fruits is there really information about all existing devi fruits in there or just known devil fruits? Will a real copy of this book come to the real world someday?
Imagine only known Devil Fruits, right? That just doesn't seem like fun if the world knew every single one of them. That's a fun idea. One would hope that a full set of Vivre Cards would itch that scratch. I think an actual tome of them would require a great deal of original creative writing from the content creation team and the approval process would be a massive undertaking requiring a significant chunk of Oda's time. Realistic aspect aside, I'd love to see it!
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! In chapter 580, Ben Beckman threatens Kizaru with a rifle. Was Kizaru really threatened or was he just joking around?
This might not be the answer you're looking for but I think the answer is somewhere between the two. Kizaru is recognizing that Ben is a badass and knows that he should be careful, but at the same time he's not exactly quaking in his (fancy) shoes. I'm not suggesting that he recognizes him as an equal, but rather someone who, if he lets his guard down, could indeed be problematic.
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! Well…let's talk about the real big question in the german community. Will Enel return from Fairy Vearth to the Grand Line?
I absolutely believe that Enel will enter the story again. He's one of those cases mentioned above where I believe Oda is avoiding using him in supplemental material because he has a very strong idea for how he wants to use him again. But also, Space Pirates!
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! Shanks and Mihawk What is really the connection between these two? Just rivals? Future Nakama? Are they both even in strength?
No idea really. There's just not enough info. I'm not even sure if Oda knows yet. Similar to the previous question, it doesn't seem like a connection that needs to be important until the story presents an opportunity for it to be Important. That's not to say their connection won't be incredibly important, but I do wonder at what stage the importance of the relationship exists in Oda's head. While I feel it's probably somewhat more established than when they first appeared together, back then I think Oda simply wanted to paint Shanks a bit clearer by helping us see that the dude who just wasted Zoro used to go toe-to-toe with Shanks back when Shanks had two arms. Could Shanks still beat Mihawk? Mihawk seems cocky but who knows, right? Those are the kinds of questions Oda wants to present and doesn't want to answer purely because of the fan speculation it will create for years and years.
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! What happened to Don Krieg and Gin? Will we meet them again? In chapter 67, G told Sanji to tell Luffy he hopes they will cross paths again on the Grand Linel
I can only imagine that Gin is having his own adventure filled with what it means to be his own man while Krieg is…Krieg might be stuck in his own delusional world where he imagines himself the hero of his own twisted story trying to strengthen himself through various means. Either that...or Gin managed to knock some sense into him and he's turned himself around. Tha would feel like the most satisfying victory because it would mean that Luffy and Sanji affected Gin in a meaningful way that allowed him to mold Krieg instead of the reverse.
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! One thing I feel strongly about, is that we'll see Gin again. Gin is essentially the series' first Law-type character who is a somewhat strong, reserved, and most importantly, somewhat sickly male. Most foreign fans haven't been around long to experience Gin-Mania at its peak in Japan, but he was a wildly popular character among first-generation One Piece readers. I don't think Oda will deny readers the chance to meet him again and it is very likely that Oda is intentionally holding him back for that very purpose. When Oda doesn't have characters return it's usually for one of two reasons that are polar opposites: He doesn't want to ever use them again, or, he has a very solid idea for how to use them. Clever fans may even be able to discern who some of these characters are given their use (or avoidance) in tertiary work such as television specials. Basically, the more you see a character in the anime, the less of a solid idea Oda has for how he wants to use that character in his own story and is comfortable with Toei using the character. THIS IS NOT ALWAYS TRUE There are always exceptions but it's definitely something of a pattern.
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! When Shanks ended the war, there was mentioned in chapter 580, that he had a scuffle with Kaido before What happened between the two Yonko?
I don't think it's very important. At least, at the time it wasn't important to Oda. What Oda needed was a reasonable stopping block so that we could believe the Kaido we're seeing in the story right now, couldn't just have waltzed into Marineford and done what he pleased. If he didn't use Shanks, there's really no other force besides another Emperor that he could've used to throw a wrench in the gears of Kaido's movement.Oda's pretty damn good at power balance so he simply took a character whose forces he thought could stand toe-to-toe with Kaido's forces and plopped him in there. Not to mention, it served double-duty because we all just assumed Shanks was away, so when he showed up, BAM!
So at that time, no, I don't think Oda came up with anything particularly important that went on. ….But that's classic Oda 101. By manipulating his characters in order to help make a pivotal event make sense (ie. 'Why didn't Kaido just show up and pound everyone at once!?') he's established a scenario that COULD be pivotal later on. Let's say he later realizes that he needed to have a scene where Shanks and Kaido meet. He'll look back at his material and see what would have been a good opportunity for such a meeting. Imagine Oda: "Where could the two have met that would've made perfect sense and that the readers would accep-OH! Yeah, that's right, I said they met back then. Perfect!" This happens all the time, and he uses it to brilliant effect!
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! You met 'The Man", the "Goda himself" How is he? Is he that genius?
Meeting Oda for the first time was one of my top 5 best memories. The first time was quite overwhelming and I didn't know how to react but as time went on and we started interacting through various mediums on various projects got to know him better and I can say with great certainty that he is most undoubtedly a living Luffy from head to toe. Well…Luffy at his most low-key. Oda is definitely one of the most chill individuals I've ever had the pleasure of meeting. He is extremely funny and an absolute pro at ice-breaking in a conversation. I performed a magic trick for him and one part of the trick requires a viewer (Oda in this case) blowing on a piece of rope which then magically stretches into a longer rope. When Oda saw the results he quipped, “Wow...my breath is awesome." He is very laid back but he's constantly absorbing information and the world around him. If that is part of being a genius, then yes, Oda is a very bright individual and it's easy to see how he is able to blend so many concepts into his stories and designs.
But man, Greg! You don't need those "German communities", you have perfectly fine Germans at home! Here, at Arlong Park!
Germans asking questions that actually matter! Like, what's the size of Shirahoshi's Sea Kings!??
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Are they as big as Zunisha? Smaller? Bigger? How many fully transformed Koidos would fit in that fat whale thing in the back!?!