Not sure if serious. Tbh i dont like debating about fights which kishi has already showed us. But allow me to break the Op's dream, nonetheless xd.um all snake summons at once and 10,000 snakes and sword that can get longer for long distance,poison can get trought susanoo Oro wins win no problem genjutsu is his only weakness and sealing well thats everyone weakness
You say 10000 snakes. Do i need to show you the image of the white snake that got cooked due to amaterasu. If itachi was to use that, all those 10000 snakes or so would turn to 10000 burnt snakes.
Also you say sword that can get longer for long distance.
If you mean this is what you mean;
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Its an easy target for the totsuka sword. Such an attack would be useless against susano, but and infact would make oro vulnerable.
Itachi didnt even waste time with oro and asked sasuke if he had another other oro orientated attack for him to seal;
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