Future Events Who will fight Jack sama senpai kun

#15
Chopper, he already said it "wanna spent the timeskip to be stronger. As long as I can be useful for Luffy, I don't mind being a "Monster"..."
Which isn't happening yet.. He just stomped his enemy in Fishman island and Perospero is a good counter for unprepared Chopper, by disabling his moves while he was still in his brain form.

As @PeperLevi also said, Chopper will prove how he is stronger than Sanji post timeskip when in this arc Chopper beats a Calamity while Sanji will have either a rematch against Page One, or a match against the strongest out of Flying Six (Calamity > Flying six in hierarcy powerlevel wise).
 
#16
First:
Cat (Neku) and Dog (Inu)
However, they will LOSE

Jack has his (hybrid) which he did NOT USE YET just like Neku and Inu (solung) which was not used. But still, Neku and Inu with their solung (which probably has a limited time because we can remember how Carrot was exhausted after few minutes from Solung). I believe that they will put down Jack, or to be more precise, they will THINK they put down Jack with their last strongest move. BUT, after few minutes, we see Jack standing back up like Doflamingo did with Law's Gamma knife, and we realize that this is actually because he's awakaned Zoan. He's able to recover faster as in Impel down stated. Which is why Jack no matter how many Ls, he gets, he keeps getting back up.

Then, we will have Jack humiliate Inu and Neku for few minutes before the interferance happens by Jinbe. Yes, you heard me. It'll be fishman vs fishman
 
#18
The two dukes they will beat him in there full moon form and eat him maybe

first round Hybird Jack vs Dukes
second round Hybird Jack vs sulong Dukes
 
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