I Killed You Before You Said I Was the Prophetic Savior?

(Ingredients of this article: no system + no heroine + light and funny + a little bit of darkness + a little bit of pretending to be a pig and eating a tiger + a little bit of sickliness) It is prophesied that there will be two sons, one will save the world and the other will destroy it. But who is the savior? Who is the one who destroys the world? ... Don't panic when you time travel to someone who is dying. Maybe he is jealous of the talent, and maybe he can awaken a unique ability. Unfortunately, the person He Yan traveled through was defined in that book as a person who would destroy the world. Fortunately, his spine was relatively good and he could withstand such a big pot falling on him. By the way, it's better than what's in the book. Definition? There is no need for the world to help him define it. How can a character in a book be qualified to define him?