It's pretty cool when One Piece creator Eiichiro Oda gets involved with the films. He produced and wrote the story for the tenth movie One Piece Strong World, and he's confirmed to be executive producing the twelfth movie One Piece Film Z, which is set in the New World.
But even if he's not crafting the story, Oda is still contributing by designing the movie's villain Z, who is described as the "strongest enemy yet." From this sketch shown in the 21st/22nd issue of Weekly Shonen Jump, it looks like Z has some sort of giant mechanical right arm. I wonder if he also has a Devil Fruit?
I'm personally not placing much stock in the claim that Z is the strongest, since the whole Devil Fruit system places more importance on different fighting styles and creative tactics than things like power levels. Eneru was overwhelmingly powerful, but essentially couldn't harm the weaker Luffy because his thunder had no effect on Luffy's rubber body. Still, I feel like any time a creator gets involved with these generally non-canon movies, the result is always improved.
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