The arguments against Carrot haven't changed - and neither has my belief that she will join.
I think there's quite a bit remaining in Wano - I'd say 40 chapters or so would be a pretty fair assessment. Beyond the battles, which may not be incredibly long aside from the main fight against Kaido, we still need to learn about Kaido's backstory, which could be a couple chapters. I still believe the Kurozumi plot hasn't been setled completely yet and fully expect Orochi and maybe Kanjuro to reappear.
Further, now that Onigashima is being lifted to the flower capital, I fully expect the unresolved plot threads (Kokeshi dolls in the basement of Orochi's Castle for example) and characters still absent from Onigashima like Hiyori will come back into play.
With an arc this long, I expect a final act (ha) denoument which is fairly substantial. The post-battle part of the CP9 saga lasted 10 chapters for example. Dressrosa also had a pretty lengthy falling action segment.
There's still the potential for an act break with further intermission chapters as well.
So I'd say early 2022 is likely when the arc will end.
Also, Carrot climbed to the top 20 fairly recently:
Her part in the story isn't finished; I don't really think it makes sense to say the fight with Perospero is the end of her character arc. Oda opened that storyline - the only reason Carrot needs resolution with Perospero is because Oda chose to open that storyline in the first place. And Oda doesn't typically create storylines which are entirely tangential. I feel like the attitude is, Oda's just ticking an arbitrary box by having Carrot resolve her story with Perospero, but the reason that story needs resolution is because Oda started it in the first place. What's the point of Carrot's story in the bigger picture of the narrative? Because Oda doesn't typically waste time on fights between tertiary characters. This isn't Bleach. Oda doesn't even spare time for the Straw Hats to have major battles in most arcs (aside from Luffy).
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@SeaOfHope:
It's a pretty steamy hot take to believe there won't be 5 Acts considering we're following a Kabuki theater structure.
Isn't this Act supposed to end in tragedy?
Greg said it might not be five acts, but that's hardly a definitive statement, and I think we're guaranteed at least 4, given that the falling action would seem to map to the 'ha' phase of a Kabuki play and certainly wouldn't fit in act 3. And so at that point, it's entirely reasonable to think there will be a split in the action at some point, breaking things into acts 3 and 4, particularly with Onigashima being airlifted to the mainland.
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@Robby:
Those things all also apply to Capone. And if you change it to Punk Hazard or Dresserossa instead of cake land, apply to a bunch of other characters.
If you're going to count volume cover appearances, Law has been on at least 9 covers, often prominently given equal billing with Luffy.
Other long runner characters like Kinemon, Momo, Rebecca, Bart and Cavendish, have three or four covers as well.
And how many has she been in out of the last 100?
For a while there KYROS was one of the 20 most appearing characters in the series, purely because Dresserossa was so long. And Hody Jones appeared more than Whitebeard. Carue appeared more than Blackbeard. Mr.5 had more appearances than Shanks.
Arcs get longer so screentime does too. How much they've gotten lately is an important factor too.
What do those same gloves mean to all the other minks that also wear the exact same thing?
Kyros actually never made the top 20 list; Post-time skip, the only characters to break the top 20 for the first time are Brook, Jimbei, Law, Kinemon, Carrot, Doflamingo, Big Mom, Smoker, and Camie. Brook, Jimbei, Law, Doffy, Big Mom, Smoker, and Camie all had pre-time skip appearances. The only characters introduced post-time skip to ever reach the top 20 are Kinemon, Carrot, and Momo. Big Mom only 'appeared' once pre-time skip though in 432, so you could also include her on the list post-time skip.