I don't believe it, but this scenario came to my mind
Orochi in 1047: *Goes insane when completely engulfed in flames*
Orochi in 1048: *Beheaded by a samurai*
Kaidou in 1050: *Falls into magma*
Kaidou in 1051-???: *Goes insane when completely consumed by magma and goes on a rampage in the flower capital*
Kaidou in 1051-???: *Beheaded by a monstrous samurai*