I know that kaguya is supposed to be the final villain and all but why does it seem that the black shadow aka black zetsu aka kaguyas will aka Wesley snipes seem to be directing every move she makes?
One can say he is her will.
But I somewhat question that, for a very distinct reason.
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Note the concentric circles indicating the Sage of Six Paths.
We must ask ourselves why the mother of two children, who voluntarily split the power of the fruit between them, suddenly had a change of heart (or a lack thereof....) and was willing to (one can only suppose) kill her sons in order to get the power back.
The answer to this can be found within the tale of the bamboo cutter.
When the feathered cloak (hagoromo) was draped across the shoulders of Kaguya-Hime, her compassion for the world fell away and she ascended with her people to the stars.
We can take a bit of artistic freedom with the idea and say that Hagoromo - the man gifted with the Rinnegan (the symbol for buddhism and the paths of human experience/cycle of human suffering) - attempted to relieve Kaguya of her compassion for the world (which was keeping her from ascending - or achieving true happiness).
Then Kaguya went ape-shit because her compassion - which would otherwise check the impulse to use force to make people stop fighting: "This is mandatory fun - you will not leave until you are happy and have fun! Fine - a world of hypnosis and character-scrubbing for you it is!" - was gone.
If we extrapolate that what was condensed to form Black Zetsu out of the Juubi's sealing (which contained Kaguya's will) was also a portion of Hagoromo's original seal... then all of Black Zetsu's behavior (including his assumption that Naruto and Sasuke met the Sage of Six Paths... because, you know, centuries old dead people regularly interact with the living) makes sense. The stone tablet (why didn't the Senju get one) for Black Zetsu to alter (alter how - it's stone) makes sense.
The only reason for the Sage to be sending himself into the future is if he had a vested interest in the outcome of that future (which is very un sage-like) - IE - something to do. He didn't ask Naruto and Sasuke "Hey, how's it going. Oh, shit - a war, you say..."
He simply said: "Hey, I know a lot of stuff about the bad things going on right now - and I conveniently have a solution for you. You don't need to know much about Kaguya other than she was a totalitarian ***** who needs to go away."
I mean... he may as well have a sign above his head that says: "I Have Ulterior Motives."