Very good analysis towards defeating Pain.
I do say Tsukuyomi'ing everybody of Pain is a very interesting thought and I think it might succeed in many ways. The only problem that Itachi would have is that he doesnt know where the real body of Pain is. I dont think that Tsukuyomi can actually kill a person, I think its just used to severely dis-orientate the victim and mentally rape him to such a state that the caster of Tsukuyomi have enough time to kill the actual person. So I think he will seriously damage Pain(The real one) but I dont think that he would be killed in the process. So Itachi would still sit with the dilemma of finding the real deal if you get what Im saying, but it would surely be a very effective ability against Pain.
Tsukyomi is a killer move.. Sharingan Kakashi said on the Hospital,after getting knocked down with Tsukyomi that Itachi Uchiha could have killed him with it
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