User blog comment:Kaido King of the Beasts/Chapter 884: Sing or Swim/@comment-31429799-20171102184721/@comment-3507581-20171102193623

Well, you see, only taking the canon (as in, appearing first in the manga and then in the anime) logia, all of them revolve around a natural force or an element; which is why the other ones introduced in media other than the manga are not akin to it since nothing that happens in movies and anime-only arcs is canon, let alone relevant to the franchise. (Check the navigation template for story arc and see.). Oda himself stated the classification in SBS vol. 30.

Also, have you ever wondered why paramecia are the most common Devil Fruit class? Because it englobes every superhuman abilities other than animal-morphism or elemental manipulation. That said, the Mochi Mochi no Mi isn't the only paramecia mistaken for logia; we have the Doru Doru no Mi, Doku Doku no Mi and the Beto Beto no Mi, but if you wonder why are these four ones being paramecia, take the fact that all of these are man-made substances unlike the logia.

And yeah, there's much tension about the fight between Luffy and Katakuri, and the supose that if Luffy wins it would be staw; paraphrasing a statement from the One Piece Podcast: "Luffy haven't really faced significant challenges post time-skip. He's gotten a bit cocky since his training and has to be humbled". I support this by saying this battle should end like his first two ones with Crocodile.