Oh I don't know..
The list is something like this:
In no particular order.
Kaguya
Hagaromo
Hamura
Madara
Juubito
Black Zetsu
Naruto
Sasuke
8th gate Gai
Asura
Indra
Hashirama
Minato
Kabuto with Edo Army
Nagato
Rinnegan Obito
regular Madara
Kakashi with Kamui
Shisui
Hiruzen/Prime Hiruzen
I think that's more or less it. I might have left out a few here or there.
My god, that is quite a few ninja.
Are you serious? Think about what your suggesting for a second, and let me clarify a few points with you because this is ignorance at it's best. Apart from Kaguya being the birth of all ninshu/ninjutsu what ever and it being passed down through generations of your so called Shinobi. Take away the given or borrowed power from everybody in this manga and then tell me who in the hell is ****ing with Itachi? honestly, are people that dumb?
1.Kaguya, well uh, duh?
2. Hagaromo/ Hamura let's not state the obvious....
3. Madara? questionable, EMS was obtained by taking his brothers eyes? now I would love to see a MS Madara vs MS Itachi... I would love to see how a young MS Madara battles against Amatesaru and gets past yata shield. Madara didn't become the madara we fear until he gained EMS, ridiculous chakra reserves, and because of EMS capable of producing a susanoo the size of Kurama. But im leaning toward MS madara before borrowed powers from Izuna sharingan.
4. Juubito ? please, once again, borrowed powered match up. Though, Obito having both his original eyes yea, pretty much unstoppable I give it to obito.
5. Black Zetsu? No...
6. Naruto? LMAO, the guy that has PLOT on his side and a infinite chakra demon? take away kurama Itachi stomps. And yes, I said it, not even his sage mode is doing it for him.
7. Baby brother? sike, MS Itachi spanks little sasuke unfortunately, Sasuke doesn't get EMS from big brothers eyes, he doesn't get Ama implanted in him from big brother. So you have MS sasuke with katon/Raikon variants and a susanoo. Either way, unfortunately, Itachi wins Via Ama, Totsuka/Yata and outlasts do to stamina.
8. 8th gate guy? knock it off, tsukuyomi ends it before Guy finished ei, in eight gate.
9. Asura/Indra sigh, stating the obvious. Why exactly out we putting gods children, and his children's, children's against itachi?
10. Hashirama beats that ass "Only other all mighty powerful shinobi who has 0 borrowed power and is just an absolute monster."
11. Minato? knock it off, gets stomped via Tsukuyomi or ama, and produces nothing in his entire arsenal that can penetrate susanoo.
12. Kabuto with edo army? df? yeah okay, talking about the king who stole DNA and power from every shinobi. Stop it.
13. Nagato, a nobody with out madara rinnegan, once again, borrowed power.
14. Rinnegan obito, borrowed power.
15. Regular madara? uhmm okay? Itachi wins.
16. Even with kakashi kamui he gets stomped effortlessly via Tsukuyomi, another shinobi who relies heavily on his borrowed power
17. Shisui mmmm possibly.
18. Prime hiruzen possibly, I don't see him countering ama, or tsukuyomi.
Anyways, you people really need to stop looking at all these cats in naruto that have been giving the most extreme power ups which lead them to be OP as ****, and realize how OP a healthy itachi really is with his own power. Then think about who really is ****ing with itachi?