a stronger wind jutsu
or a combination
A stronger wind jutsu since its the only elemental affinity he has.
Thats a cloud of dust from where his attack hit the mountain or whatever it is.
I doubt it's wind. I think it is "that jutsu", the one Jiraiya told him not to use. Naruto already hinted that he wanted to perfect/complete "that jutsu" with Nature Energy/Hermit Mode. He didn't tell Fukasaku about "that Jutsu" when he asked about Naruto's comment, and again we see Naruto not wanting anyone to know about perfecting this new jutsu, even Fukasaku. I don't believe "that jutsu" could be wind, or any other element for that matter, because Naruto didn't start learning and training elemental chakra until well AFTER the time skip that we know of. He also knew very little about elemental chakra at the start of his wind training.
I don't think he is "hitting mountains with jutsos" when he is training secretly and making sure noone sees him
He probably just created a special summon, or a huge powerball of some sort.
In the world of the blind, the one eyed man is KING!
I don't think it's an Element Jutsu....It could some we haven't before. Something he couldn't use unless he had access to the Kyuubin power. But, now since he has a new power source for the jutsu he was just testing it and trying to improve it.
Well, that's what I think.
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