I think jiraya could have been revived BUT: Nagato was out of chakra, well, nearly out of chakra and he had to concentrate on a whole village of ppl to revive which costed him his life. I assume that the longer a person is dead, the more difficult is to bring him back. Nagato was already a lot fatigued by what he had to do and if he tried to bring Jiraya back too he would have died out of effort before achieving his goal, leaving Jiraya ,in fact, dead.
I know Rin died long before Jiraya, but there are two options:
1.If nagato used his power with full chakra and having to focus on one person only, even if long dead, he could have revived Rin.
2.Nagato was going to be linked to gedo mazou someday (or am i wrong?) so he could have used the biju chakra to bring her back.
Kinda makes you wonder why he never brought Yahiko back to life....even here i see 2 possibilities:
-There is a time beyond which you can't revive a person anymore.
-He intended to do it, but he waited until their plan reached completion.
Of course I could be wrong, but it might be possible.
@Lakritze
I kinda understand you, but I'll tell you what i did tell always. Just wait for the story to develop and maybe Kishi will explain things better leaving you satisfied in the end.
1. Well, we don't really know to what degree was it all by chance. I believe Madara had a high contribution in the setup of the events. I still don't know how much but I hope we'll learn about it.
2. To obito Rin wasn't just a classmate. I though by now you'd understand it. He was a bit obsessed with Rin...she was clearly the most important person to him, otherwise he wouldn't have achieved MS. The dearest person to him was killed by his best friend, who was supposed to protect her. This adds quite a big of shock effect and traumatize a youg mind like Obito's. I believe it's all madara's plan, and that Zetsu is influencing Obito's character.
3. I agree with you about this. Hashirama cells are way overused in this series.
About Zetsu/Yamato...i don't understand either but i do hope kishi explains it to us after Kabuto comes back from Izanami.
There might be just one original zetsu, used as a vessel to create the clones, in other words, the first white zetsu that was created by madara.
Of course Yamato could be related to the uzumaki or senju. I also wonder why doesen't he like using his normal name Tenzo. Does it hold some meaning to the plot?
About Obito's redemption...I always liked Obito as a character and he was my favourite, so i really hope he will be redeemed but not in a normal way like happened to Nagato. I hope his change of heart will be complicated and unusual. Not by talk-no-justu, but by other means, like Madara's betrayal or such.
My friend, i know many things are off and make the story a bit.....ridicolous, but wait until Kishi tells us all the story to comment on that

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