Since the latest chapter there have been many speculations about which devil fruit Kaido has.
While I certainly like the idea that Kaido is a dragon with the Oni Devil Fruit it still leaves the question why Oda changed Kaido’s design since his first appearance…
… unless he hasn’t!
Many people have been speculating that Oda has used the old Kaido design for Ashura Doji, who changed his name to Shutenmaru after Oden’s death (this is just a theory i’ve heard a lot) and went back to his old habits of being a bandit.
On the other hand we have this theory that speculates that the new Kaido design is just his human-dragon hybrid form:
Lastly before I tie everything up it is important to mention that Shutenmaru is exceptionally strong if he can go toe to toe with Jack and it is also interesting that Jack says that the Beast Pirates have left him alive for such a long time because Kaido wants Shutenmaru to join his crew.
So what’s going on? Oda didn’t mess up or change Kaido’s design and neither is it a coincidence that Kaido (in his old design) and Shutenmaru look so much alike. Kaido and Shutenmaru are actually brothers!
*Theory by Papa-Yaga
