So I seem to see a lot of people have different opinions on how sasuke got his rinnegan. Some people say he got it because the sage of the 6 paths have it to him. I may be wrong but I thought he unlocked it because kabuto implanted hashi(ashura) DNA to save sasuke life and since he was near death and ashura chakra mixed with indra chakra. And I thought that the chakra that the sage gave him is what caused his rinnegan to have the 6 tomes. And having basically 2 eyes in one. Because based on the requirement. Sasuke wouldve awakened the rinnegan regardless if the sage gave him chakra or not. But a lot of people think he only has his rinnegan because of the sage . I think that is incorrect.