Board Thread:Naruto Discussions/@comment-36006024-20180926134241/@comment-31099706-20180927120342

The only other guy I see as natural as Guy and Lee would be Jiraya. But it maybe that he was also blessed with powers, since he was also a student of Hiruzen and had the strength to kick away a snake and such.

Simply put, there are three types of geniuses in Naruto. The ones that are born with unnatural talents, like Itachi, Kakashi, Minato, Hashirama, Madara. Then there are also talented shinobi but had to work hard to reach most of their potentiel, like Neji and Sasuke and probably Hiruzen. Then I guess there's the last one, that is those who trained until they became geniuses in that field(If that's a thing), like Naruto and Lee.

Power ups, like EMS and Tailed beasts might be counted as an external source. But when you look at it as tools, they fit the user. Sasuke used Itachi's MS after his death, the chakra being used for it is coming from Sasuke, and not any external source. Naruto gained the control of the Nine tails, and uses it's power as his tool. Tools are of shinobi. So it should count.