Luffy's Gear 4th

Gear 4th is the last gear theory

If we take a look at THE LATEST CHAPTER 784

 we can 

see that Luffy said in order to fight monsters he 

became like that.That means that he only used gear 

4th to fight monsters and did not use any other 

gear. This could also mean that he didn’t come up 

with a new gear because he handled the monster 

with his gear 4th already.

 that would mean that gear 4th is the last gear that Luffy came up with and has no new gears such as gear 5th or others. I’m not saying there won’t be any more gears, but he just hasn’t come up with new ones yet. He doesn’t have a gear 5th up his sleeve.

But, that doesn’t mean that he won’t come up with new ideas later trough the series. He might use a new gear in a fight with the yonko.
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