@Daz:
At this point I keep imagining Elbaf as that one island in Wind Waker which was all "Uh this place got wrecked by Ganon, heres the macguffin you need, what do you mean "ran out of development time"?"
But nah, while I do expect Oda to hit the gas even more than he's already doing, I don't think he'll ever go full Toriko. But I do think a lot of the "bullet points" will be handled quite expediently- a lot of "wow that was quick, but I guess that wraps up [X]"
And this is totally cool and I'm okay with that. As long as it is answered within the confines of the story, I'm personally okay with what he does. Like I said, be it 2 panels, 20 chapters, or an arc (lets say 80-100 chapters as the last 3 major ones have been), hopefully everything will be.
There are a ton of things (the bulk of OP's mysteries in fact), that can be answered together. However, there are a lot of unrelated plot threads between characters that I can't personally see being combined exactly into one arc. I do believe Elbaf (and possibly, Vegapunk if its at all separate from anything else), are the last significant arcs (i.e. greater than 40-50 chapters) this series does outside of the final war. Things like Lodestar/Laugh Tale/God Valley are possibly all tied to the final war, Zou sized or just featured in other ways such as flashbacks or other characters (Lodestar/God Valley in this case)
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@FelRes:
Using arc algebra instead of arc calculus, could also look at how he transitions storylines around hundred chapter marks. Chapter ~1000 something big like Luffy vs Kaido or crew completed with Yamato or whatever, Wano goes on then off to Elbaf and around ~1100 they got all the road poneglyphs and wrap it up around ~1200 and call it a day. So however long it takes to get there. A lot of bullet points are gonna get steamrolled together and a lot of people are gonna be like "oh" when it happens.
But thats under the assumption that the manga will end quickly. You either get 1 or 2 different flavors (unfortunately). You get something like Yu Yu Hakusho or a variety of other manga where it just get bullet pointed to the end (like you are saying), or you get Naruto/Bleach and the final arc is over 30% of the entire series' volume. Oda quite literally has to stuff over a hundred character arcs/threads in what looks to be the final conflict. Unless you expect the former, its most likely the later, but the most important thing is trying to meet it halfway, not to short and not too long.
Personally I don't believe One Piece is ending before Chapter 1300. We are 13 chapters away from 1000, and Wano probably will last till at least 1040-1050 at the rate it is going. That still leaves us with a healthy number of chapters and considering past actions, I believe Oda will build it slowly again, like he did for Alabasta, Marineford and now Wano over multiple arcs. You have to escalate the Strawhat's involvement in the final war, build emotion, etc. It's part of the reason why many people think the Final War really isnt' starting post- Laugh Tale because clearly Roger couldn't stop whatever he wanted to by finding OP too early. Now its the right time for Luffy to find out the same thing and be involved.
IMO, and its silly, but I personally think (obviously don't take chapter numbers seriously):
- Wano: 909-1050 (highballing it to 140 chapters)
- Vegapunk: 1051-1100
- Elbaf: 1101-1180
- Lodestar: 1181-1190
- Laugh Tale (including the sail to the region it exists): 1191-1210 (perhaps this is included in the final war
- Final War (New Marineford/Mariejois/Fishman Island/God Valley): 1211-1300/1400 (anywhere in the middle)
This is the thought process I've had for awhile. I am pretty adamant on Vegapunk/Elbaf being somewhat significant because of Bonney and Urouge being the only 2 supernova without focused arcs. They could happen together though. Hell Vegapunk's lab could be on Elbaf (or Lodestar). We just know its not on Marine HQ/Mariejois, because Akainu barred Fuji from returning until he caught Luffy, and we know he dropped off Smoker/Tashigi (whom weren't with him at Mariejois so it can't be there). Lodestar I feel like is necessitated by the journey (its a geographical milestone, they should sail there). But it will, at most, be the length of Sabaody with something significant happening before Laugh Tale. Laugh Tale depends on what happens there, but I feel like it won't be horribly long, just incredibly majestic with the chapters we get from it. From then on, the Final War makes sense IMO, but it could happen during the conflict with Blackbeard/Im/Akainu. I do have this weird feeling that everything ends on God Valley though. Rocks was there for a reason (aside from killing the Tenryuubito), and I think BB/Shanks will be present. I'm not sure if Laugh Tale was ever meant to be "end" of the story.
Its all incredibly unknown as of yet, but that is so far exciting to me, because I know I'll be wrong.
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@Sengokusgoat:
Fishman Island I think really is the best comparison for what to expect from Elbaf. Mostly a bunch of exposition and lore about giants and their history, and how they tie into the grand scheme of things, with some not super major but still dangerous threat that can allow Usopp to become a savior in their eyes. Incidentally Fishman Island was also an island that was built up for a lot of years.
The giant tree I expect to be the most important aspect of the island. It so impossibly huge (it literally extends beyond horizon in some panels of BM's flashback: https://i.imgur.com/NsBJn6s.png)