And now about this version of the evolution of the sharingan, I agree in everything except where you say:
I still think that it comes with experience: In battle and in training, especially after all in
Naruto the author established a strong relation between Chakra - Experience and Skill, we can see this during the first volumes of the
manga. And of course we can't forget that Sharingan itself consumes chakra and the Magenkyo Sharingan consume even more Chakra(I mention chakra due his relation with Skill/Talente/Physical abilties, etc...).
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