One Piece's latest episode marked a major turning point of the battle between Luffy and Katakuri as each of them has reached another level of power after it seemed early on like Katakuri would only dominate.
But as Luffy says he's figured out the trick to Katakuri's power, fans watched as Luffy broke down Katakuri's technique and almost get to the root of where he draws his strength from.
As he was battling against Katakuri in Gear Fourth, Luffy remembered when Rayleigh taught him about Haki. He remembered that the Color of Arms Haki allowed him to hit even Logia Devil Fruit Users (users that become a particular element, and don't seem to have a physical body), so he had been wondering how even his Haki punches weren't landing on Katakuri.
It turns out that Katakuri had trained his Color of Observation Haki to such a degree, that when he predicted that Luffy would attack, he had formed his mochi body to move around those punches. So although it seemed like Luffy's attacks were punching straight through Katakuri, it was Katakuri really predicting the moves and dodging accordingly.
But Luffy managed to hit Katakuri a few times right after he interrupted Katakuri's Merienda, and this was because Katakuri had lost his cool. The Observation Haki only works when Katakuri is calm, and when Katakuri calms himself he's able to dodge against Luffy's attacks once more.
Now that Luffy has found the trick behind Katakuri's dodges, he still has to find a way to work around Katakuri's predictions in order to finally succeed. But it's not going to be easy as Katakuri has ramped up his efforts as well.
Eiichiro Oda's One Piece first began serialization in Shueisha's Weekly Shonen Jump in 1997. It has since been collected into over 80 volumes, and 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 over 430 million copies sold.
Oda revealed some news about One Piece's future in a recent interview as well. Stating that he was about 80 percent done with the manga at this point with the Wano arc, fans are worried that the series may be coming to an end sooner than they thought. But it wouldn't be wrong to infer that the ending will most likely still be years away given how much of the world there is to explore and just how well it's selling week to week.