I think there's no such thing as a coincidence when Pluton is supposed to be deep underneath Old Wano, a "Pluton" in geology is a rock body formed underground in magma chambers, and Big Mom and Kaido are currently inside of a magma chamber beneath Old Wano. Kaido even talked about the ancient weapons during Onigashima. The end of this cover story may tie into kaido and big mom breaking down Wano's borders with Pluton and heading to Elbaf or attempting to raid Marie Geoise themselves.
Maybe Pluton is living in the volcano where they are, and Kaido and Linlin + Pluton are just... floating together in magma?
We could see Linlin + Kaido + Pluton at the end, leading into Teach attacking Wano.
We know Uranus needs a Mother Flame to run: IMO, Pluton does, too, and, to make up for that, it's using the energy from the volcanoes to fuel itself in its slumber (I believe Pluton is a Sea Beast Submarine, a Turtle turned into a Sub, foreshadowed by Crocus hollowing out Laboon's insides and turning Laboon into a makeshift submarine.
If Crocus can do it, the Ancient Kingdom sure as heck could, too.
If Pluton is in Wano's Underworld, which is full of magma, Pluton should be swimming in magma. Pluton being able to move through veins of magma would be very dangerous: are you familiar with the concept of undermining? Not the word, but the actual dangers of digging under an area excessively?
undermine(v.)
c. 1300,
underminen,
undermynen, "excavate beneath, form a mine under, render unstable by digging at the foundation," from
under +
mine (v.1) "dig." The figurative sense "injure by invisible, secret, or dishonorable means" is attested from early 15c. Similar formation in Dutch
ondermijnen, Danish
underminere, German
unterminiren. The Old English verb was
underdelfan. (seer
delve). Related:
Undermined;
undermining.
https://www.etymonline.com/word/undermine
IMO, Pluton EATS the Underworld of countries, and causes them to collapse into the ocean. Uranus attacks islands from above, we saw this with Lulusia. Pluton crawls underwater/underground, even through lava (it's probably a turtle dragon... TURTLE DRAGON?!?!?)
Pluton eats the foundation of islands, so they then sink, or drift off into the ocean.
If the Beast Pirates are mining underground for Kaido (explains King being shown in a dark place during Vegapunk's yap-factory), they could very well lead to seismic collapses within the Regions of Wano. Since Udon is a mining region, I believe we'll see their efforts soon.
Furthermore, the bombs in Onigashima are still there, as far as we know: I think Jack will dive down to Onigashima, take out the bombs Yamato froze (should be thawed by now), and then use them to try to excavate Kaido out.
Seastone is formed when Pyrobloin from magma/lava mixes with seawater; due to the cracks in Wano's bedrock from Law's Puncture Willie, Kaido and Linlin, and the bomb that fell into Linlin's Magma crater, water should have seeped down into the bedrock, and then mixed with the magma to form Seastone. IMO it will be weaker than refined Seastone, and can be mined easier.
IE: I think the Beast Pirates fucking around with mining and bombs in Udon (where Yamato is) will cause an explosion/boom soon.
I KNEW ODA WASN'T DONE WITH THOSE FUCKING BOMBS
Teach and Zunesha are on Border duty (also Crocodile since he can dissolve the borders into Sand)
Alright, I had never even thought of this till now: if Pluton is a ship, ARE THERE PEOPLE LIVING INSIDE OF IT? Like, Ancient Wano and Water 7 workers who helped build Pluton to begin with? IMO the ship will be made out of Seastone, and Wano helped build it, like Shandora's City. There very well might be Ancient Kingdom Remnants living in Pluton.
Once again, CROCUS LIVES IN A WHALE, anything is possible in this series.