This chapter was fire !!!
Kaido and the supernova praising Luffy's haki just goes to show how special it is, and considering that the only person we know to use it is Rayleigh just shows how rare it is.
The only great men Kaido considers to be capable of fighting him are Rocks, Roger, Whitebeard, Oden and Shanks, so Shanks and Kaido have fought before, this only hypes Shanks
The dynamics between Zoro and Killer, and Luffy, Kid and Law were great...its a shame Bepo isn't there
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With Kaido going back to his dragon form, I get the feeling Oda wants to skip this fight for bit to focus on the other strawhats and side characters, and when we return he will.