WARNING: The following contains spoilers for One Piece Chapter 1032, "Oden's Beloved Blade," by Eiichiro Oda, Stephen Paul, and Vanessa Satone, available in English from Viz Media.
The difference between a Zoro vs a Luffy fight is that Zoro is relied upon to defeat the opponent in front of him, while it's not always certain that Luffy can defeat his foe. Zoro is the second mate and that means getting handed heavy responsibilities by his captain, and, luckily, Zoro hasn't had that many close calls since the time skip. Until now, as in Chapter 1032, Zoro has his back against the wall when facing Kaido's right-hand man, King the Wildfire.
We see on the outside of the dome, King has taken to his Pteranodon devil fruit form to get an aerial advantage on Zoro. The next page then shows what might be the best sequence of panels in all of One Piece. King starts pulling back on the back of his skull, further and further, to the point that his beak is being retracted back into his skull. King lets go and his beak recoils at tremendous speed, destroying the earth and stone around the swordsman. King that remarks this method was how the pteranodons of the past used their prey which is deeply disturbing, but even funnier when Zoro believes him.
Zoro tries to shoot a 360 Pound Pheonix slash at King, but he manages to nimbly dodge out of the way. Zoro realizes blindly attacking will only wear himself out so he goes for a different method and uses Black Rope Dragon Twister to knock King out of the air. King, however, is clever enough to use his massive wings to shield himself from the tornado of slashes.
King then leaps down in his hybrid form with a massive sword of his own, intrigued to partake in a proper sword duel. As he parries and blocks King's slashes, Zoro assesses King's abilities, particularly his odd flame manipulation and those massive wings, trying to figure out a weakness.
Because King said his pyrokinesis is not related to his devil fruit, Zoro surmises it must be an ability related to King's race, such as giant or fishman. With a slam from King's blade, Zoro is sent flying, crashing into a massive boulder that comes clean apart. As he lays bare on the ground, catching his breath, Zoro begins hearing a melody, clear as day, played on a shamisen. In the very next moment, Zoro's newest blade, Enma, engulfs in flames, and that's where Zoro's battle leaves off in this chapter.
It's not quite clear what caused Enma to start burning, but it could be related to Hiroyi playing on the shamisen. Enma was originally one of the katanas belonging to Kozuki Oden, so it would make sense if Hiyori knew more about the blade's secrets, given that she is his daughter. For now, we'll just have to be patient, but it's great to see Zoro getting serious when faced with an adversary pushing him to his limits.
