To begin, Hagoromo said that Kaguya utilized both of her doujutsu to cast IT the first time around. It isn’t elaborated on what role the Byakugan played there but we can assume that the sharingan casted the genjutsu on the populace, in this case.
Now when Madara casts IT, his own Rinnegan are reflected in the eyes of the populace as opposed to the Juubi’s sharingan, despite the moon having the sharingan projected onto it:
In essence for Madara’s case, the Juubi’s sharingan is only useful for making the moon the catalyst for the genjutsu to be projected onto and creating the illuminating light that shines through all things. As Madara describes:
Which is also why a mere Rinnegan is all that’s needed to defy the IT genjutsu, Much like a Mangekyou sharingan and Uchiha blood can defy Tsukuyomi.
Anyway, when Sasuke uses his Rinnegan to cast genjutsu on the Bijuu, his Rinnegan is reflected in their eyes which includes the tomoe:
Therefore, if the Juubi’s sharingan is what had cast the genjutsu rather than just being a medium, then the tomoe would’ve been reflected on the eyes of the populace as well.
Sasuke even confirms that Madara’s Rinnegan is what casted the genjutsu:
-Extras-
-Edo Madara’s fake Rinnegan reverted to a sharingan to cast a genjutsu on Ay
-Momoshiki’s Rinnegan didn’t have any tomoe yet his Rinnegan had casted the “genjutsu” onto Boruto. That whole scenario is still a cluster **** though.
-Sasuke’s Rinnegan genjutsu didn’t give Sakura a Rinnegan pattern in her eyes, for whatever reason. Much like when Obito put Konan to sleep.
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Now when Madara casts IT, his own Rinnegan are reflected in the eyes of the populace as opposed to the Juubi’s sharingan, despite the moon having the sharingan projected onto it:
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In essence for Madara’s case, the Juubi’s sharingan is only useful for making the moon the catalyst for the genjutsu to be projected onto and creating the illuminating light that shines through all things. As Madara describes:
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Which is also why a mere Rinnegan is all that’s needed to defy the IT genjutsu, Much like a Mangekyou sharingan and Uchiha blood can defy Tsukuyomi.
You must be registered for see images
Anyway, when Sasuke uses his Rinnegan to cast genjutsu on the Bijuu, his Rinnegan is reflected in their eyes which includes the tomoe:
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Therefore, if the Juubi’s sharingan is what had cast the genjutsu rather than just being a medium, then the tomoe would’ve been reflected on the eyes of the populace as well.
Sasuke even confirms that Madara’s Rinnegan is what casted the genjutsu:
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-Edo Madara’s fake Rinnegan reverted to a sharingan to cast a genjutsu on Ay
-Momoshiki’s Rinnegan didn’t have any tomoe yet his Rinnegan had casted the “genjutsu” onto Boruto. That whole scenario is still a cluster **** though.
-Sasuke’s Rinnegan genjutsu didn’t give Sakura a Rinnegan pattern in her eyes, for whatever reason. Much like when Obito put Konan to sleep.
You must be registered for see images
You must be registered for see images