I was thinking about the fact that Luffy often fights the 4th strongest of a crew or organization before facing the strongest one. Meanwhile Zoro and Sanji fight the 2nd and 3rd strongest member respectively.
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An example of that would be:
Baroque Works
Crocodile defeated by Luffy – Mr.1 defeated by Zoro – Mr.2 defeated by Sanji – Mr.3 defeated by Luffy
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CP9
Lucci defeated by Luffy – Kaku defeated by Zoro – Jabra defeated by Sanji – Blueno defeated by Luffy
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This generally happens when the Straw Hats fight against a big organization or crew.
Another strong point to this theory is this:
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90% of the time that Luffy says he will beat someone, he always defeat that character. Examples like Crocodile, Doflamingo, Katakuri, Lucci, Moria etc.
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Finally I would like to extend on this theory with (I think) a foreshadow of how Luffy will defeat Jack. Like we all know Luffy has learned Advance Armament Haki to be able to defeat Kaido.
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I think Luffy will test this new haki on Jack and he will defeat him exactly like Rayleigh defeated the elephant when he was training Luffy.
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So that’s it. What do you think?
*Theory by Rozava