Honestly I doubt anyone is in there. I believe the question about bowel movements is what was supposed to let us know it's the spiral zetsu shell from before. It was eerily timed perfectly with a recent anime release where obito first met spiral zetsu and was asked by him "what does it feel like to poop"
alot of people think that it is yamato and i agree because as madara said the white zetsu are a WEAK copy of hashirama and there is no other explanation to how the spiral zetsu summoned the giant statue thing with the 1000 hands other than yamato boosting the white zetsu at least this is how i explain it to myself
Honestly I doubt anyone is in there. I believe the question about bowel movements is what was supposed to let us know it's the spiral zetsu shell from before. It was eerily timed perfectly with a recent anime release where obito first met spiral zetsu and was asked by him "what does it feel like to poop"
Hmm maybe, but there's some things that just doesn't make sense. Whether the kages was fully recuperated or not, the zetsu would still have to face the likes of Jinton, Raikage's speed and strength, and Mei's KKGs. You may argue that the statue could have done all the work, but regardless... doesn't this make this spiral zetsu a front-line fighter? In fact, doesn't it make him very high kage level?
It seems both zetsus (black and white) shown so far are weak in battle prowess compared to some other shinobi. There's that much of a difference between spiral zetsu and his counterparts?
Both zetsus is apparently created using mazou and Hashirama's cells.
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^Keep that in mind, now look at these Viz panels.
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Base denotes foundation, a bottom, the "core". How is it that spiral zetsu is the base when it was created in the same manner as the other zetsu? That's the only way it would make sense if there's no one in it, that the other Zetsu was created from the spiral zetsu. Spiral zetsu would have to be the "base" of all zetsus.
Didn't we see earlier that people are capable of wearing it like a costume? Doesn't Occam's razor suggest that by "base", someone is in it?
Look at Oro:
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Wouldn't it be anticlimactic if it's the spiral zetsu we knew of all along? Also, your post doesn't really take away from the possibility that someone may be in it. As it's true that it was to show that we are looking at spiral zetsu, however, that doesn't mean there's no one in it.
Edit: Also, why would Obito not bring him to the battlefield if he could perform such jutsu and take on high-ranking kages? Obito was wearing that spiral zetsu even after Madara died. And it wouldn't make sense that Madara wouldn't want Obito with those powers after leaving the power of the rinnegan and SO6P's jutsus in his hands. It's most likely because spiral zetsu couldn't perform jutsu of that scale until after he acquired this "base".
seems likely kabuto did use him to supercharge the zetsu army which is destroyed now anyways so it could be that spiral zetsu picked him up and used it to enhance his mokuton powers.