You kinda have to take it on faith...not everything is PROVEN in manga, this series is a prime example of it. We KNOW hamura is Hagoromo's brother and we can assume he is boss but is it proven?
1. Size doesn't necessarily translate to power; being able to convert a large amount of power into a smaller, more focused form can be an advantage.
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In essence, Naruto and Sasuke have converted massive (each potentially Juubi-level!) quantities of chakra into their respective avatars, while Hashirama decided to convert his huge supply of chakra into the largest possible Mokuton avatar.
2. Hashirama has stated that he is weaker than Juubito, who possessed less Bijuu Chakra than Sasuke's Susano'o at the time Sasuke fired Indra's Arrow. Since Naruto was able to rival this arrow with his attack, it's likely that Naruto is on a similar level.
Cites:
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3. While I stand by my statement that the size of one's avatar doesn't necessarily translate into that avatar's strength (relative to a more focused avatar, etc.), I still feel the scale of Naruto/Sasuke's clash is pretty persuasive evidence that their power is on a greater level than Madara/Hashirama's.
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4. Madara's Susano'o/Kyuubi combination, which Hashirama defeated, is a bit different than Sasuke's Susano'o / Bijuu Chakra combination; Madara's Susano'o was not strengthened by the Kyuubi's chakra, and merely acted as a suit of armor. I would argue that this made it easier to destroy than Sasuke's; therefore, while Hashirama's Shinsusenju managed to defeat Madara's Susano'o (and thus allowed Hashirama to put the Kyuubi to sleep with his technique), I don't think the same would necessarily work on Sasuke's Bijuu-empowered Susano'o.
5. Large-scale Mokuton is not necessarily durable enough to combat the current Naruto / Sasuke.
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Keep in mind that not all Bijuudama are created equal; if the average Bijuudama could have inflicted this level of damage to the Shinju, then Killer Bee / Naruto would have been able to destroy the tree much sooner. I would argue that this Magma Rasenshuriken had more power behind it than the average Bijuudama.
Anyway, I believe that, based on these feats (and several others shown during the Kaguya fight), Naruto and Sasuke have each surpassed Sage Mode Hashirama and his Shinsusenju.
A yoton rasenshuriken powered by rikudou chakra & senjutsu of the six paths, which then managed to bisect the progenitor of all chakra in it's final form is weaker than a bijuudama created by a creature weaker than it? Not a chance.
1. Size doesn't necessarily translate to power; being able to convert a large amount of power into a smaller, more focused form can be an advantage.
You must be registered for see images
In essence, Naruto and Sasuke have converted massive (each potentially Juubi-level!) quantities of chakra into their respective avatars, while Hashirama decided to convert his huge supply of chakra into the largest possible Mokuton avatar.
2. Hashirama has stated that he is weaker than Juubito, who possessed less Bijuu Chakra than Sasuke's Susano'o at the time Sasuke fired Indra's Arrow. Since Naruto was able to rival this arrow with his attack, it's likely that Naruto is on a similar level.
Cites:
You must be registered for see images
3. While I stand by my statement that the size of one's avatar doesn't necessarily translate into that avatar's strength (relative to a more focused avatar, etc.), I still feel the scale of Naruto/Sasuke's clash is pretty persuasive evidence that their power is on a greater level than Madara/Hashirama's.
You must be registered for see images
4. Madara's Susano'o/Kyuubi combination, which Hashirama defeated, is a bit different than Sasuke's Susano'o / Bijuu Chakra combination; Madara's Susano'o was not strengthened by the Kyuubi's chakra, and merely acted as a suit of armor. I would argue that this made it easier to destroy than Sasuke's; therefore, while Hashirama's Shinsusenju managed to defeat Madara's Susano'o (and thus allowed Hashirama to put the Kyuubi to sleep with his technique), I don't think the same would necessarily work on Sasuke's Bijuu-empowered Susano'o.
5. Large-scale Mokuton is not necessarily durable enough to combat the current Naruto / Sasuke.
You must be registered for see images
Keep in mind that not all Bijuudama are created equal; if the average Bijuudama could have inflicted this level of damage to the Shinju, then Killer Bee / Naruto would have been able to destroy the tree much sooner. I would argue that this Magma Rasenshuriken had more power behind it than the average Bijuudama.
Anyway, I believe that, based on these feats (and several others shown during the Kaguya fight), Naruto and Sasuke have each surpassed Sage Mode Hashirama and his Shinsusenju.
Great reply didn't knw people like you exist in NB.
I pretty much agree with you except the Juubito stronger than Hashirama part.
If I remember vividly Hashirama said he wasn't brought back at full power considering he couldn't use Shinsuusenju.
I think that's why he said Juubito was stronger than him.