Please note this is Itachi before his death, so his illness still applies, which means he’s not at the levels he would be if he was healthy or edo tensei, otherwise this would be a curb stomp in favour of Itachi and Kisame. Just one I thought up on the fly and thought it might be fun to discuss.

I personally think it could go either way, as neither Itachi (before his death) or Kisame are individually enough to take down Pain imo. I don’t believe itachis genjutsu would affect pain and tsukyomi wouldn’t be enough for Pain either because he has the superior dojustsu. And Kisame’s water jutsu can be absorbed too. But maybe together they can take him down with their already considerable individual power and teamwork to take the paths of pain down?

Feel free to discuss as I’m not overly sure. Maybe I’m wrong and it’s an easy win one way or the other but let’s see what everyone thinks :)