Whole Kaido/Yamato relationship felt undercooked. Don't feel like he sometimes planned for a long time but made on the spot in the middle of the arc
We need Kaido's actual flashback to understand his behavior towards Yamato. Kaido's parents, and Kaido's relationship with Rocks.
Rocks clearly had a huge influence on Kaido.
Kaido's character will make more sense once we get his flashback + the full God Valley flashback.
If Yamato does go underground in her Cover Series, there's a chance she gets to talk to Kaido, too (I still think he and Linlin are trapped in naturally occuring Seastone forming from the lava mixing with ocean water that seeped in after the earthquakes).
Kaido and Linlin could be just in magma, still, though. King wouldn't be able to help despite his body, because of his Fruit; being submerged in any liquid will negate Devil Fruit powers, not just seawater. If Kaido and Linlin are in magma, they'll be weakened because magma is technically a liquid. Linlin is just a fucking unkillable entity, and we already know Kaido can handle high levels of heat from his Flame Dragon Torch.
I wanted Kaido to be in Seastone originally, but, IMO, magma fits better: like Oden, Kaido is doomed to boil to death in a "pot" of magma.
Yamato, who became "Oden" through watching Oden be boiled, will be the one to discover her father, Kaido, being "boiled" to death by Wano itself, through Mt. Fuji.
Then, I hope we get Yamato and Kaido discussing shit. Kaido still has no idea Yamato had Oden's journal, the shit he was looking for for fucking years.
Also need Gloriosa, Yamato's Mom, to show up, too. Where the fuck even is Boa Hancock? Probably headed to Elbaph to fuck Luffy...