

This is a pretty tricky fight and both of these fighters are some of the strongest Shinobi in the series. Itachi’s sharingan gives him a big boost, but Pain’s Rinnegan is also formidable. Pain’s bodies help to give him the edge since Itachi would eventually be overwhelmed. His array of jutsu is impressive and Itachi is physically a match for Pain as well. Pain’s ninjutsu would just be too much for him to overcome. Pain wins.
Well the pain bodies have been shown to be able to be put under genjutsu. And Itachis Izanami has beaten Kabuto who is greater than Pain or Nagato. And while the bodies are under a genjutsu itachi could find nagato and take him out with amaterasu since he would be in that machine he couldn’t move very fast enough
Ah, but since it’s composite, Nagato is in his prime so he can still put up a fight as well. The genjutsu part is an interesting angle, but I believe that they would be able to fight if off with the Rinnegan now that they are aware of it. Nagato in his prime is a pretty good match for Itachi, which is why I believe the Pain bodies would turn the tides in his favor!
But, I still think Itachi would win. Why? Because he’s an amazing tactician. Naruto used strategy against the Paths in order to fit in hits that would defeat them in one shot. With his Sage Mode on, he could kill a Path, as demonstrated, with one solid punch due to his enhanced strength. Itachi, being the best tactician in the series(likely only rivaled by some of the Naras), would find more opportunities to fit in fatal blows. We already know Itachi’s arsenal consists of mostly fatal techniques when he wants to truly kill a foe. He’s been shown to utilize weaponry such as the Ninja-to during the slaughter of his clan, or basic kunai while infiltrating the Leaf Village. These two weapons are fatal per direct hit, while even from a distance, faster than Naruto’s rasen-shuriken, Itachi has Amaterasu, which commonly ignites instantly on eye contact. He can utilize Amaterasu to large extents, as seen when he fights Sasuke, he surrounds the entire hideout with eruptions of Amaterasu, as Sasuke outruns it, never able to stop.
The only threat is the Deva path. Naruto fared so well against the Deva for so long, because he had to re-charge his abilities to their fullest extend after diminishing the Leaf Village to rubble. If we’re talking about Itachi in the prime of his abilities, he could easily summon Susanoo, and the sword of sealing, and the Shinra Tensei would not work.
If we’re talking about Itachi at the peak of his illness, he would most likely save his Susanoo as a last resort, and try to pick off each Path one by one. This lessens his chances of winning dramatically, but being the strategist he is, I think he’d be capable of defeating Nagato and his paths still. The only thing I see Itachi falling to is the pain from the overuse of his own abilities. So basically Itachi wins, or he kills himself.
Nagato is not much of a strategist, although he did figure out how to get into the village. The powers of the Rinnegan are not as potent because they’re spread over the course of all six people, meaning anyone can remove any of his powers one by one.
This battle would depend if itachi knew prior to pain’s abilities or not.
And also if it was nagato who is fighting him or the six paths of pain with nagato in a paper tree somewhere.
First lets tackle the six paths of pain.
Starting with itachi having no prior knowledge to pain’s abilities.
In terms of power output i would say the six paths of pain would have an advantage, mostly thanks to deva and asura path and i guess animal path too.
Though as trevor pointed out itachi has a lot of instant kills moves like ameterasu and the totsuka blade.
However the part where genjutsu would work on the pains, technically its a yes or no, the pains can still be put under normal genjutsu, but visual genjutsu, well not really. Considering how the rinnegan could resist the effects of the infinite tsukuyomi, a genjutsu far more powerful and dangerous then itachi’s tsukuyomi, its unlikely tsukuyomi or itachi’s visual sharingan genjutsu’s would work, after all the genjutsu jiraiya had casted on the pains was sound based not visual based.
In speed itachi could react to lightning attacks and i guess pain could too, its still unclear though
As for itachi’s susanoo, well its probably the deciding factor for this fight. its a decision if itachi can actually deal with all 6 pains before he runs out of chakra or deva path hits him with that shinra tensei. or the preta path absorbs the susanoo chakra. or the fact that animal path summons thousands of beasts to battle the susanoo.
So for this fight i would give itachi’s win rates 3/10
Now if itachi did have prior knowledge to pain’s abilities and pain knew itachi’s then itachi’s it would probably be split between them
5/10
Now if this battle was nagato and itachi,
(bare in mind no prior knowledge for either of them
Then again it would also be a split issue. i mean ameterasu would be useless considering nagato could use shinra tensei to repel it or just absorb it.
tsukuyomi like i said would not have an effect
But what about itachi’s susanoo, well as mentioned, the animal path would be a “Pain” to itachi because itachi would constantly be forced to seal away animal after animal, hell this is assuming nagato gets a hold of itachi’s soul and yanks it out, or absorbing itachi’s chakra.
Now for itachi’s win conditions he is a lot smarter, and would probably be able to figure out nagato’s abilities much faster then nagato can for itachi’s. and one stab from the susanoo totsuka blade can end nagato’s life fast. But that’s really it, most of itachi’s abilities would either be absorb or pushed away from shinra tensei, and itachi at close range could get his chakra or rip his soul out.
While itachi could figure out a plan to catch and stab nagato with the susanoo
Overall for this fight itachi’s win rates are a
4/10
With prior knowledge, again its kinda a even matchup or itachi’s win rates are
5/10 or 6/10
Update
Unfortunatly i have to drop itachi’s chances fighting nagato by quite a bit, but lucky for itachi him fighting the six paths of pain will be buffed
Six paths of pain
Itachi win rate
4/10 or 5/10
Prior knowledge for both characters
itachi win rate
5/10 or 6/10
Nagato
itachi win rates
3/10
Prior knowledge
4/10 or 5/10
The reason i buffed the paths of pain was because the paths of pain actually had weaker abilities compared to nagato alone.
Which is why nagato gets a buff and the paths of pain get a nerf. Afterall itachi could keep pace and match kcm1 naruto, a mode where naruto is much stronger compared to his sage mode counterpart. Sure this was reanimated itachi but the reanimated versions of shinobi are weaker.
I think the toughest thing for the paths of pain is that Jiraiya was able to do so well against them. He had a few of the bodies on the ropes and I can’t picture Itachi not doing much better than that. With the sharingan and his natural speed it should be a cakewalk to deal overwhelming damage here. All he has to do is keep laying on the pain and that will be the end for some of the Pains but I agree that defeating them all would be a little too tricky
Definitely a good write up there. The battle definitely opens up a whole lot of possibilities on who would win and what strategies to use. It could really go a lot of different ways but taking on all of the bodies would be brutal. They would be able to coordinate perfectly with their shared vision and so Itachi’s genjutsu would not be super effective here. Trust in the process and all but even Itachi would start to doubt his abilities