I just wanted to share my thoughts in regards to my perception of Luffy as a Conqueror throughout the New World, and why he is thematically and physically able to achieve this level of Conqueror’s Haki. Forgive me if this ends up being a long read.
First off, I believe that Luffy’s affinity and aptitude towards Conqueror’s Haki is well shown to us as the readers. I believe this has some substantial ground to it, not simply because Oda said Luffy’s specialty is Conqueror’s Haki in an SBS. If you look throughout the New World, Luffy has pretty much consistently been building prestige as a very powerful and influential pirate; all of which, has occurred in a short period of time.
Luffy first started off claiming Fishman Island as his own territory from Big Mom; therefore, this was his entry point into shoehorning his name into the New World.
Afterwards, he began to form an alliance with Law to take down one of the Yonko: Hundred Beasts Kaido. Punk Hazard and Dressrosa were both an effort to build to Kaido’s downfall, while simultaneously building even more prestige for Luffy by building his Straw Hat Fleet of several New World pirates. Of course, then comes Whole Cake Island where Luffy essentially declared war against the Big Mom Pirates; which, led to Big New Morgans declaring him as the Fifth Emperor of the Sea.
Now, moving on to Wano, Luffy was taken down by Kaido in Act 1 with the Thunder Bagua. Then, in comes the Udon Prisoner Mines, where Luffy was able to not only learn about the flow of Haki but was able to influence and motivate the other prisoners. One Piece Chapter 949 “Mummy” is the chapter where Luffy really grounds himself and builds his own prestige in the eyes of the wano citizens and samurai. I feel this chapter in particular was the first chapter where Luffy was able to take himself to the next level as a conqueror in his own right. Looking back on previous arcs, Luffy doesn’t go out of his way to motivate people to his side; rather, they simply choose to follow Luffy for a singular reason and that’s it. In this case, Luffy was able to actually relate to the other prisoners due to being subdued or defeated by Kaido; therefore, Luffy was able to connect with them in the way he did while displaying his next level as a Conqueror.
Fast-forwarding to the present, Luffy has now gotten a solid grasp on the concept of controlling the flow of his Conqueror’s Haki. This concept, I believe, is shown not just through his time training in the Udon Prisoner mines, but also displayed through his acts as a Conqueror throughout the New World building up to this point. Wano is the arc where I feel Luffy has truly begun to solidfy his prestige and position as an Emperor or Conqueror of the Sea. Luffy learning to focus his Conqueror’s Haki to coat his body is, I believe, a parallel to what he’s shown as a Conqueror in the Udon Prisoner Mines. The way how Luffy was able to ground himself and bring the samurai and prisoners to his side was the moment his aptitude for being a conqueror began to show its face.
So, in a manner of speaking, instead of forcing his Conqueror’s Haki outwards to influence others, Luffy has now gotten a more grounded and focused approach to apply his Conqueror’s Haki. This is what, I believe, Oda has established to explain why Conqueror’s Haki is Luffy’s specialty; throughout all his actions in the New World, he has been building himself continuously up to this point. Now Luffy is able to fight his best against Kaido himself. A true clash of Conquerors.