Naruto chapter 661.
So............
How's Madara going to be beaten now?(Is sasuke going to somehow live, then seal madara?)
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Ugh.....kishi just going to go with the "rainbow" ending I see.
I hope not, I think Sasuke is the worst character in Naruto. If Madara ended up getting beaten by Sasuke I would seriously cringe.
I really doubt he's dead. There's 2 ways this can go IMO:
1. That was just a Genjutsu (we saw both their eyes doing something right before that happened).
or
2. Gaara brings Naruto to Sakura so she can heal him, and she somehow sees what happened to Sasuke too, and then she has to chose which one she heals.