I know this is one of the most controversial topics out there but I recently came across a reddit post/theory (not linking that post because the person ends it in saying that Wano will have 5 acts and in act 5 it will be Luffy vs Sengoku and Zoro vs Kaido) and like most theories where the current story is related in some way or loosely based on a Japanese folktale etc. this one really caught my eye. If there are some Japanese here or someone more knowledgeable on this subject please enlighten us. The link is here https://yokai.com/ootakemaru/
It is the story of Otakemaru who is an oni and to defeat him the samurai requires three sacred swords, two of these are provided to him by a goddess (whom he later marries). He kills him once (chops his head off) but the oni comes back after some time and he has to kill him again (again chops his head off) and then the head is locked away somewhere.
It is a very bad summary (mine) and the actual story maybe even bigger than what I read but I just thought that will all the threads that people have made about this theory I have so far not come across any reference to this legend/folktale.
It is the story of Otakemaru who is an oni and to defeat him the samurai requires three sacred swords, two of these are provided to him by a goddess (whom he later marries). He kills him once (chops his head off) but the oni comes back after some time and he has to kill him again (again chops his head off) and then the head is locked away somewhere.
It is a very bad summary (mine) and the actual story maybe even bigger than what I read but I just thought that will all the threads that people have made about this theory I have so far not come across any reference to this legend/folktale.