Do you guys think they'll unlock an advanced Haki ability during their fights with King and Queen or will they just defeat them at their current level?
They definitely need to if they ever want to reach the status that Rayleigh or Scopper Gaban had. Rayleigh is shown to be a master of all forms of Haki. So far Zoro is good with Busoshoku, seems decent in Kenbunshoku, but can't even control his Haoshoku.
It would make the most sense for Sanju to advance his Kenbunshoku during Wano.
I'm really not sure. I think it would be boring if they learned the abilities that Luffy already has (future sight, busoshoku lv. 2, 3). Zoro seemingly has Haoshoku now and could learn to control it, but what good will basic Haoshoku do? Sanji I'd like to see get an ability that hasn't been seen yet.
I fucking hope not lmao. Kaido said only the best of the best were capable of it. Luffy with G4 and level 3 Busoshoku was treated like a joke by Kaido, and Kaido assumed someone on his level had no chance of using it. King having it would be ridiculous.
The black blade was already brought up before the war so that could be the most likely option. Maybe Zoro will learn to control Haoshoku after beating King and can use it to knock out a bunch of weaklings. I don't see any other use for it now.