-The Wano arc opens up with an amazing accomplishment by Zoro that is a callback to an earlier scene in the series between Zoro and Mihawk (whom Zoro is seeking to surpass to become the greatest swordsmen), showing how much Zoro has grown since the beginning of the series.
-Zoro forms a bond with Hiyori, a character central to the injustice of this arc’s plot. The daughter of the martyr of this arc’s story. Zoro’s bond with Hiyori is deeper than any bond he’s had with any major character of… any story arc so far in this series. Zoro’s connection to the people wronged in this arc runs deeper than his connection to any of the people in peril of any story arc in this series so far. And after spending so long largely ignored in the last few arcs, Zoro is featured much more prominently featured here.
-Zoro, of all people, agrees to give up his precious sword Shusui because the people of Wano believe a curse has befallen Wano for the removal of this sword from its burial site. In real world time, OVER 10 YEARS AGO, Oda had Zoro cross paths with Ryuma’s corpse (the original owner and wielder of Shusui) and because of this Zoro brought back Shusui to Wano and allowed this national treasure to be restored to its rightful resting place. We are told that a legend in Wano is that Ryuma slayed a dragon.
-After this, Hiyori gives her sword from her father (Oden) to Zoro. We are told Oden is the only one who has been able to wound Kaido. And Oden wounded Kaido with the sword (Enma) that Zoro now wields. The reader gets a visual cue of Oden’s damage done to Kaido with a big, glorious X-mark (just screaming to get slashed up again, I wonder who will slash at that spot again?) on Kaido’s body.
-After receiving Enma, Hitetsu tells Zoro that people unfit to wield it would be rendered a husk attempting to use it and telling Zoro that if he were to master it, the sword could become even stronger from becoming a full black blade. Zoro reflects that by the time he has gotten used to the blade, he will be that much stronger. The comments here from Zoro and Hitetsu essentially imply that Zoro will have received a power-up by mastering the sword and taking it farther than it’s ever gone before by causing it to become a full black blade. How far did this sword go before being fully utilized? It wounded Kaido, said to be the only thing that has wounded Kaido. So how far will it go once properly mastered by someone carrying the will of revenge on Oden by Oden’s daughter, Hiyori?
-Right after the reader is taught that mastering this blade will yield in a power-up for Zoro, we see that Luffy has got a hang on the power-up he has been seeking to damage Kaido. So we see these two, Luffy and Zoro, have gone to a higher level (Luffy) or will be soon reaching a higher level (Zoro with mastering Enma) are being primed to work together to defeat Kaido
-Just a bit earlier before the events of Zoro receiving Enma, Zoro is with Hiyori as they watch Yasuie die (in chapter 942), there is a unique placement of dialogue over panels farther setting up Zoro’s role in taking down Kaido. The townspeople watching Yasui’s death comment that no one in 20 years has been able to “take Kaido’s head”. The dialogue “take Kaido’s head” is placed in a panel showing only Zoro. This whole arc is about all the effort that has gone into waiting for this golden moment that would come 20 years after Oden’s awful death. Again, with Zoro’s connection to Hiyori (and the rage he shows at Yasui’s death) we have never seen Zoro so intimately close with the people so central to the conflict of a story arc. Orochi was only able to kill Yasuie because of the power and safety net Kaido provides him. As Oden learned in his flashback, to get rid of Orochi, you must defeat Kaido. To avenge Oden and Yasuie and take out Orochi, Kaido needs to be taken out
