I see some flaws in your post. First one was that you decided that Mei and Tsunade would be working alone while they have teammates. Oonoki makes Gaara's sand and the Sand Gaara makes in the area lighter and faster and Gaara moves both Mei and Tsunade out the wayHow does Sasuke triumph in this battle?
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Eien No Mangekyou Sharingan Sasuke can beat them all at the same time. You people do not understand the veracity and potency of his Amaterasu mastery, let alone his obvious unlocking of Perfect Susano'o.
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Sasuke has shown to manifest many different shapes with his Amaterasu and Enton variants. Mei and Tsunade have not shown to be of the faster caliber Shinobi, and as such, don't have sufficient reaction feats to lets say.... Dodge an Enton Arrow? Said arrow had to be countered by Kamui (Kakashi) or he would have been gone. This is the same Kamui that was able to dislodge the entire arm of the Gedo Mazou of the Juubi in a split second before it was instantaneously reverse summoned via "Kuchiyose No Jutsu" by Uchiha Madara [You must be registered for see links][You must be registered for see links]. Needless to say, they are absolute non-factors in this fight, and are easily dispatched making this fight a 3 on 1.
Concerning Ohnoki;
Ohnoki is the only person of the Kage that can damage Sasuke's Perfect Susano'o, much like his abilities were utilized in their battle against Uchiha Madara. However, Ohnoki, even with flight, is a sitting duck to Amaterasu (not to be confused with Enton). The only people who have actively dodge Amaterasu are Ei because of his speed (and the only ones who rival or surpass are Uchiha Obito, Uzumaki Naruto, and Namikaze Minato) and Juubi Jinchuriki Obito via sensing [You must be registered for see links]. Ohnoki possesses neither of these and therefore is susceptible to a blatant Amaterasu strike, one to which he possesses no ability to negate or evade.
I'd like to point out that Jinton isn't, well, fast and can easily be evaded on foot by someone like Sasuke. Of course, before I state how this is possible lets take a look at Sasuke's speed feats.
We have seen that Madara was able to escape the Jinton on foot [→ 1] The first feat I would like to bring up is in his battle against Deidara. In this scan, Deidara is just as big as Sasuke's head [You must be registered for see links] and then he suddenly appears in front of Deidara, shocking him without the latter even realizing when Sasuke made the move. [You must be registered for see links] He even commented on Sasuke's speed by stating ''He's fast!''.
→ 2] Sasuke is standing right bellow Deidara [You must be registered for see links] and then suddenly he appears behind him. [You must be registered for see links] Deidara has no idea when Sasuke got behind him and is shocked, barely escaping his attack.
→ 3] Sasuke and his team appear to be as big as the prisoner's arm [You must be registered for see links] and then Sasuke suddenly appears behind him while cutting his chest open and both Karin and Suigetsu now seem a little smaller than Sasuke's head. [You must be registered for see links] He covered such a distance in a blink of an eye.
→ 4] Deidara is forced to use Shī Tsū because he thinks that 'Sasuke's movements are definitely too fast'. [You must be registered for see links] Please look at Deidara's size and the Dragon's size. [You must be registered for see links] Now check out the size of the explosion. [You must be registered for see links] Sasuke escaped the explosion and Deidara comments on his speed once again, saying 'Damn, he's fast!'.
→ 5] Next, Sasuke appears to be half the size of Naruto's head. [You must be registered for see links] Same can be said for Naruto. [You must be registered for see links] Then suddenly Sasuke appears down, holding Naruto's shoulder and shocking him. [You must be registered for see links] Yamato comments on his speed. Sasuke covered such a distance in a flash [You must be registered for see links] while Sakura didn't even notice when he made the move given her comment. [You must be registered for see links]
→ 6] This may or may not be as impressive as the Shunshin feats above, but I'll still add it. Sasuke was capable of evading Bī's attack [You must be registered for see links] and Bī comments on how no one except Ēi was capable of avoiding Bī's attack.
→ 7] At the Kage Summit, Sasuke was capable of appearing in the meeting room and no one was capable of noticing it until he made a cut on one of the curtains which shocked those present in the room in that moment. [You must be registered for see links] Please note that he was fast enough to cut all three of the curtains in the room present at that time as well.
→ 8] You can see that Sasuke's head is almost as big as Sakura even though he is running. [You must be registered for see links] Both Sasuke and Naruto, who is in his Kyūbi Chakura Mōdo, are running towards Sakura to quickly reach her and then Sasuke suddenly appears next to her before Naruto does and Sakura is shocked given her '!'.
→ 9] Naruto is falling and Sasuke is no where in sight [Top panel] while Obito is trying to hit Naruto [You must be registered for see links], shocking him. And then suddenly out of no where, Sasuke appears and uses Susano'o to protect Naruto which in return shocked the latter. [You must be registered for see links]
→ 10] Sasuke and Itachi are on the other side of the cave, holding Kabuto's snakes. [You must be registered for see links] And then suddenly, Sasuke appears behind Kabuto and takes off his hood. [You must be registered for see links]
→ 11] Sasuke is standing and the Samurai are a few meters in front of him. [You must be registered for see links][You must be registered for see links] And then suddenly he appears behind the Samurai, making a clean cut and shocking the Samurai without us or anyone else even noticing when Sasuke made a single movement. [You must be registered for see links]
→ 12] Suigetsu and Juugo are a meter [Maybe less] from each other and are about to make their attack [You must be registered for see links] and then suddenly, Sasuke appears between them, restricting their movements. [You must be registered for see links]You must be registered for see links], leaving only a damaged part on his clothes. [You must be registered for see links] However, the Jinton managed to touch Madara only because Madara wanted it to touch him. [You must be registered for see links]
Of course, we also have to take Sasuke's Sharingan into consideration which will allow him to predict the Jinton attack, which he already has knowledge on, and counter it much like Kakashi did against Kakuzu's Atsugai. [You must be registered for see links] It even allowed Kakashi to intercept a lightning bolt flying at high speed. [You must be registered for see links][You must be registered for see links] Not to mention that Kakuzu, himself, stated that the Sharingan predicted his attacks.
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We also have to consider Ohnoki's stamina which is rather, well, bad. He can't just keep on spamming Jinton. Ohnoki claimed that he used up his Chakra against Muu [You must be registered for see links] despite only using just one Jinton [You must be registered for see links], one Weight Technique [You must be registered for see links] and flying the whole time. [You must be registered for see links] This tells me that Ohnoki's Chakra reserves aren't really big. He could still use Techniques such as that Rock Fist technique, but he couldn't use Jinton anymore. One more thing; Amaterasu versus Jinton. There is a reason as to why I believe Amaterasu could overcome Jinton. If Sasuke used Amaterasu on the Jinton itself, I believe that the Amaterasu would devour it just like it devoured Sasuke's Katon.
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Due to the charging time of Jinton (since it does not happen instantly), any sort of external factor can halt it completely [You must be registered for see links] When Muu was about to fire off a Jinton, KCM Naruto quickly flew (Shunshin) behind him and forced Muu to "sense" him, and in turn intercept him, rather than turn the jutsu towards him; this effectively cancelled the technique via an external factor.You must be registered for see imagesDealing with Gaara and Ei.
Gaara is one who is the only person that can actually sponge any attacks from Sasuke, but there is a fatal flaw... Uchiha Sasuke's Enton Sword used with his agility in his legged Susano'o. [You must be registered for see links] In just that form, Sasuke was able to take out a massive chunk of the tree with a quick swipe. That being without Enton added to the sword. With Enton and the veracious agility he seems to display with Susano'o, repeated swipes with Perfect Susano'o and an Enton Sword would eventually break through Gaara's defense and finish off the Kazekage.
Anyways, we have to consider Gaara being capable of saving the rest of his team potentially. It doesn't matter really, an Enton Blade or a simple Enton Arrow would suffice. Sasuke has already shown to be capable of firing off multiple arrows at once. [You must be registered for see links] These arrows are so fast that Kakashi was forced to use Kamui to send them away. Gaara's only chance is to try and defend himself and his teammates with a sand defense, however, it means absolutely nothing.
Slicing nor piercing Enton based attacks cannot be blocked due to the Enton being capable of piercing slicing through solid objects like a knife through butter. [You must be registered for see links] Since it cannot be blocked or evaded by the likes of Gaara, Tsunade, Mei nor Ohnoki, all of them would either get killed by an Enton arrow or sliced in half by an Enton blade.
There's also the fact that Gaara cannot fight effectively while trying to defend the others at the same time nor can they be alert of a sudden Amaterasu at all times since they will be fighting Sasuke's Susano'o who will be smashing around, forcing all of their focus on the Susano'o and in other words; giving Sasuke a chance to pull off a sudden Amaterasu and kill them with it.
Also, while defending, the active Enton can be controlled by Sasuke. That's the point of Blaze Release. Sasuke has full control of the shape, size and "speed"/location of it. He can actively move it, especially if it is on something. So for instance. If Gaara enacts to save the Female Kages, the Enton quite clearly won't get eradicated from the Sand, and Sasuke can directly coordinate from there where he'd want the Enton to land.You must be registered for see images
Ei is the only one in the fight who can dodge Amaterasu/Enton, but the same can't be said for an Enton coated V3 Susano'o with legs. I doubt he has the strength to take any portion of it out (Tsunade, who is physically superior to him was only able to crack V2 of Madara's Susano'o. Nothing indicates Ei can rival that at all, and in turn, not break Sasuke's Susano'o at all). So continuous Susano'o Sword Swings (if you choose to say coated in Enton, will end him, or he will get reckless and charge in and be coated in Enton as he can't enter the vicinity of the Susano'o).
As for Ei's V2, yes, he may be capable of evading the Amaterasu when he uses his V2, however, 4th Raikage had to inject Bijuu level chakra into his Armour to up it to V2. Unless he has Chakra reserves bigger than ninetails, he isn't keeping it up for more than a minute. Not a chance. Because of the chakra invested. The V2 Cloak requires far too much chakra. How can be maintain something like that for too long? It seems statistically impossible. Look at it this way, in BM Naruto is capable of keeping up the avatar for 8 minutes and no more. Whilst not exactly a similar thing, the analogy is still valid, as BM has its own chakra capacity.
Raikage cannot possibly have a bottom less chakra supply to maintain something that consumes such a large amount of chakra. The longer he maintains it, the more chakra he consumes. In fact, has he ever used V2 for large extended periods?
Raiton Armour is just like Nagashi. The only difference is that the Raikages have such a large chakra pool that they are able to continuously generate Raiton from their body and use it as a defense and speed enhancer. So it constantly eats chakra. Add V2 into the equation and you can do the math.You must be registered for see images
The rest.
Neither Mei nor Tsunade would be a problem. Neither of them so far haven't shown to be capable of reacting to something like Amaterasu and will rather easily be defeated by it. The Enton Magatamas can be used to deal with both of them rather quickly. [You must be registered for see links]
There is also the fact that Tsunade is basically useless and that her attacks would only result in her own death. She needs to actually punch the Susano'o directly in order to do something. Considering that Sasuke would coat the Susano'o in Enton, all she would do is get Enton on her hand which would force her to chop it off, leaving her without a hand.
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Well, if Sasuke doesn't decide to make the Enton travel to the rest of her body, of course. And that also applies to Ei, as that is his fighting style, which is suicide against an Enton coated Susano'o.
As for Kirin this is what it took to prime Kirin -> [You must be registered for see links][You must be registered for see links][You must be registered for see links]
2 Katon in the air and 1 use of Amaterasu. Now think of this fight, and how much Amaterasu will be used, on top of Sasuke's possible use of normal Katon? Kirin would be primed in no time.
What happens when Sasuke just decides to shoot off a few Enton arrows into the sky? Kirin is pretty much gathered immeadiately and it will be more powerful than the one Sasuke used against Itachi.
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And to people disregarding the fact that Sasuke has Perfect Susano'o... [You must be registered for see links]. Madara's Susano'o clearly has the elongated nose on his Tengu demon.You must be registered for see linksSasuke clearly has the same Tengu, AND the same sheathed swordYou must be registered for see linkswhich Madara possessed on his Susano'o as well. And to further validate this, Sasuke exclaims in the previous panel that "You must be registered for see links". More so, Hashirama immediately recognized it. And before discrediting the size, Perfect Susano'o has taken on a different shape each time it has been fit around the Kyuubi. Sasuke had to literally coat Kurama (Naruto) and was around it, as opposed to it fitting closer to size. Same with Madara [You must be registered for see links]. Both times the larger Susano'o had to be fitted to the smaller Kurama. So with this definite evidence of Sasuke possessing Perfect Susano'o.... Ei is not much of a problem at all. His fighting style is negated by the massive construct and he, along with the rest of the Kages will be annihilated if they haven't already before this.
Sasuke is the victor.
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Credit goes to Transcendence and AkatsukiChurch.
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. You also said Oonoki have low chakra, this is wrong, in fact he has a ton of chakra. His first Jinton was
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and then as the Edo kages and SA charged at each other, Muu and Oonoki flew off to fight each other, they been fighting off screen
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. As you can see from the surroundings, and Oonoki panting, they have been fighting
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. Then him and Gaara were fighting the 2nd Mizukage
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where he was low on chakra and his Jinton cancelled. After that he made all the sand around them lighter and even made the first meteor lighter
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. Plus even though Tsunade healed them, Gaara and Oonoki weren't at full power when fighting Madara yet Gaara was able to block about 5 complete Susanoo's sword while saving Mei.Mei can use hidden mist to weaken Sasuke's sight as she was doing to Madara
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so that will make it harder to aim at them. Oonoki tag teams with A by making him lighter and even faster while he can charge his Jinton while A blitz close to him or use a collaboration jutsu to break Sasuke's complete Susanoo
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.Sasuke's complete Susanoo did not, I repeat did not cut that large branch by it self. Sasuke had Yin-Yang chakra increasing his strength. Kakashi's Kamui power was increased by at least 3x the power when he got a little bit of chakra, Kakashi said Naruto gave the alliance even stronger chakra (could be around 4x-6x+) because he matched it to each person's chakra and we see Hinata jutsu strong enough to knock the Juubi's tail by herself. Then Choji mentions how the Yin yang chakra was even stronger, so Sasuke's power was increased about 7x-10x+.
Also Sasuke has yet to show how well he can handle PS, Stable of unstable, on his own. We got a 1 time use so can't assume he can use it like Madara did against the kages. As of now that's spectulation at best. All of the kages were weakened and tired when Madara pulled out PS, When Oonoki saw the God tree he told the Donton users to use the earth under it to knock the tree down, same can be said about the PS. Can also use the giant Jinton that wiped out 25 complete Susanoos in 1 blow, but aim for where Sasuke will be in PS if he can use PS well enough to use it.