Devil Fruit: Everything you need to know
The idea of acquiring multiple powers by consuming multiple Devil Fruits is quite enchanting, but it is strictly prohibited. So much so, that it is a fundamental rule to not possess more than one Devil Fruit in the world of One Piece. If one does, it would result in an unexplained immediate death. This aspect maintains balance, adds mystery, and leads to adventures, thereby making it a significant nuance of the show.