The Whole Cake Island has been a favorite arc to lots of One Piece fans, but with as much damage Luffy has been causing throughout the arc fans have been wondering how much his bounty would build up to after everything is said and done.
If one fan theory is to be believed, Luffy's bounty could cross the one billion Berry.
Reddit user KhornKT, Luffy's track record throughout the arc could mean his bounty has nearly doubled since it was last counted. He defeated Cracker, who was worth 860 million, and now he's fighting Katakuri, who's already worth one billion. So assuming he takes down Katakuri at the end of their fight, his Berry worth could cross the one million mark.
Then if word of ruining Big Mom's wedding gets out, as well as causing a ruckus on her island, that could lead Luffy's bounty to raise as well. Factoring in the fact that Luffy might fight the next of the Four Yonkou, Kaido (who has already been teased in a previous chapter), the a one billion bounty for Luffy could make sense.
Katakuri is a strong opponent, and Luffy seems to be matching his strength blow for blow, so it would only make sense to have Luffy reach at least the bounty level of someone who serves as the right hand to a Yonkou.
Given that the Yonkou's bounties are all in the upper billions, if Luffy were to be seen as a real threat to them (which could very well be the case after his tiff with Big Mom and her crew) then a high bounty would make a lot of sense. Either way, Luffy's current bounty of 500,000,000 Berry is certainly going to change.
Eiichiro Oda's One Piece first began serialization in Shueisha's Weekly Shonen Jump in 1997. It has been collected into 87 volumes, with a few chapters yet to be included. It has been a critical and commercial success worldwide with many of the volumes breaking printing records in Japan. The manga has even set a Guinness World Record for the most copies published for the same comic book by a single author, and is the best selling manga series worldwide with 430 million copies sold worldwide.
Eiichiro Oda also revealed some upcoming news for One Piece's future at Jump Festa 2018. Not only will the manga see Wano sooner rather than later, the next villain of the series is "one of the legends which lurks in the One Piece world. The greatest enemy ever for Straw Hats will hinder their way...Can you believe Marineford Summit War will look 'cute' compared to that?"
One Piece is currently in the middle of the "Whole Cake Island" arc and is now streaming on Crunchyroll and FunimationNOW.