The thing about One Piece is that you will never know what the character will look like until Eiichiro Oda decided to drop the bomb. I honestly thought of Shutenmaru in a very different character design. It was shocking to see his real character design in One Piece chapter 921. Since Kaido is already in the area, will Shutenmaru ally with the Yonkou to save his and his men’s lives? Or will he let the Samurai Pride and will fight against Jack and Dragon Kaido?
If Kaido is indeed the dragon in the last chapter (not a projection, a weaker clone, or any substitute), then Shutenmaru being there would pique his interest. After all, the reason why Shutenmaru is still alive is that Kaido wants him to join the crew. Shutenmaru is a powerful addition to Kaido’s men and can fight eye to eye against Jack, who is one of Kaido’s most powerful subordinate. It seems like Kaido will be the one who will ask him to join in One Piece chapter 922.
Will Kaido actually join the Beast Pirates? If he refuses, all the people in the town and all his men will be in danger. But since the pride of the samurai runs through his blood, it is likely that he will refuse Kaido and will choose death over being a slave to the Beast Pirates. A battle might ensue and Shutenmaru might die in One Piece chapter 922, unless, Luffy and the crew will help him escape.
It can be remembered that Kiku seems to know Shutenmaru and she might convince him to join the Anti-Kaido-Orochi alliance. Hopefully, Shutenmaru will join the alliance because they actually need more people for the upcoming coup d’etat. With Kaido looking like that and Big Mom coming to Wano, this will be a hard war for the Straw Hat Pirates.