How does this show that Itachi would or could beat Kaguya? Itachi wouldn't have time to use another genjutsu if IT is sued since he would be in the genjutsu when it's activated and so would his crows if he tried using them. Sasuke said a genjutsu made from the Rinnegan most likely can only be cancelled with another Rinnegan
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This means Tsukuyomi and KA are useless against IT. You haven't given any way Itachi can do against Kaguya who can freely use COAT and just drop Itachi in a volcano
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She can literately make anything she wants out of nothing with COAT, she could make weapons much stronger than the Totsuki blade and yata mirror like a blade that can cut through any defense and destroy what it cuts and a shield that absorbs whatever hits it and can even send attacks back at the enemy
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