Our second favorite sensei from Naruto (Guy is first, obviously), Kakashi Hatake, is famous with fans and within the Naruto-verse. Popularly known as Kakashi of the Sharingan, the Team 7 sensei is one of the show's strongest characters. Kakashi's popularity is no surprise since he is the only known character, except Danzo, to possess a Sharingan without the Uchiha gene.
Fans of the show will remember that Kakashi was given the Sharingan as a gift from his dying friend Obito Uchiha. Even though Obito was out wreaking havoc, creating the Akatsuki, destroying the Leaf Village, and getting the Fourth Hokage killed, when he gave his Sharingan to Kakashi, he did think he was going to die. Of course, we only find out later that Obito was alive and pretending to be Madara for years.
Of course, Kakashi being the ingenious prodigy that he was, mastered the abilities of his left eye over the years. He used the copying abilities of his Sharingan so well that he was reputed to have copied over a thousand techniques, which led to his nickname as "Copy Ninja Kakashi." At some point during Naruto: Shippuden, Kakashi also masters the use of his Mangekyou Sharingan, an ability that benefits him greatly during the Fourth Great Shinobi war.
However, since Kakashi was not an Uchiha, fans have wondered how Kakashi could awaken the Mangekyou Sharingan in the first place. Read on to find out.
The answer to how Kakashi awakened Mangekyou is pretty simple: he didn't. That's right, Kakashi Hatake never awakened the Mangekyou Sharingan, even though he could use and master the technique.
It all goes back to when Kakashi was still a young boy before joining the ANBU. After his teammate and best friend, Obito, died, saving him from being crushed under a giant boulder, Kakashi performed missions with Rin Nohara. During one such mission, Kakashi and Rin head off to Kirigakure, the Village Hidden in the Mist, where the latter was forcibly turned into the jinchuriki of the three-tailed beast, Isobu.
Kirigakure planned to have Rin enter the leaf village to break the seal and have Isobu wreak havoc there. Seeing no way out of the problem, Rin begged Kakashi to kill her before that happened. Kakashi, who valued his friends more than anyone, refused Rin's request. Adamant to save the village from destruction, Rin jumped in the way of Kakashi's Chidori, which was meant for a Hidden Mist ninja. Thus, the powerful Chidori cast by Kakashi took the life of one of his closest friends, Rin, awakening the Mangekyou Sharingan.
However, Kakashi was not the one who awakened this ability. What nobody knew at the time was that Obito, who was still alive, had just arrived at the scene only to watch Rin die at the hands of Kakashi. Obito, devastated by Rin's death because of his love for her, awakened the Mangekyou Sharingan, thereby granting Kakashi's ability, who wielded his left eye.
Well, you knew this wasn't going to be a happy story when you read the word "Sharingan." In any case, Obito and Kakashi's Mangekyou Sharingan is one of the most powerful ones of its type. Both eyes wield "Kamui," which teleport targets to and from Kamui's Dimension, though in different manners.
During the Fourth Shinobi World War, they discovered that each eye was impervious to the others' Kamui. The right eye, wielded by Obito, can use close-range Kamui, teleporting the user and those they're in contact with. On the other hand, the left eye, wielded by Kakashi, can use long-range Kamui, creating a barrier around a target that teleports them and producing an attraction force to draw other targets close enough in.
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