Itachi Uchiha(イタチ,
Uchiha Itachi) is a
missing-nin from
Konohagakure, and a prominent member of Akatsuki, partnered with
Kisame Hoshigaki. He is Sasuke Uchiha's older brother.
Personality
Itachi is a mysterious character and often acts as though he is concealing his true self. While flashbacks to his past show that he was a compassionate brother and person, his later acts and claims make it seem that this was mostly just an act. But, surprisingly, he actually is the compassionate brother he once claimed to be, but he hides this to protect his brother. When he openly challenged the clan's ideas, he showed some degree of anger but never lost his composure.
As a member of Akatsuki, he possesses incredible self control of his emotions. He constantly displays an emotionless personality, though at times, he appears to have a slight degree of anger or frustration on his face. He only shows surprise when opponents prove more powerful or skilled than he had expected, and even then he doesn't lose his composure. He does not possess any arrogance, and fully justifies any statements he makes about his power, and even compliments his opponents on their abilities. Despite his status as a wanted criminal and having murdered a significant portion of his family, Itachi has no enjoyment of violence or combat, instead preferring to avoid battle or, if this is not possible, end it as quickly as he can.
Itachi's only initial interest is in Akatsuki's goals and his only loyalty appears to be to the organization and its members, putting the organization's success and secrecy before everything else.
[11] As such, Itachi gets along with his partner, Kisame, much better than most other Akatsuki members do with their own partners. Kisame, in fact, has a deep loyalty to Itachi, immediately doing as he instructs and constantly looking out for his well-being. Itachi treats all of his fellow Akatsuki members to this same, more respectful personality, although his courtesy is rarely returned by the other members.
However, when he is in a Genjutsu duel during his fight with Sasuke, he agressively and violently claims he only let Sasuke live so he could take Sasuke's eyes and obtain his own Eternal Mangekyo Sharingan, and then he claims the Uchiha Clan is nothing but tainted and evil since many members would kill their friends to gain the Mangekyo Sharingan, and take another Uchiha's eyes to make its power permanent. Once the Genjutsu is released, he calls it his true self, implying his calm, emotionless personality was also a facade.
Madara, however, later reveals that this is not the truth. Itachi really was the caring brother that he once claimed to be only an act. He had killed his clan only because he had been ordered to by Konoha to stop the Uchiha from rebelling against the village or else Konoha would order other anbu to kill the clan instead. His childhood experience in war had caused him to greatly fear the violence the Uchiha could cause, so he made the incredible sacrifice, and decided to murder his entire family, creating the image of his "evil" side that so many had known him to be. Deep down, Itachi had cared a lot for Sasuke, so he never revealed the treachery of the Uchiha Clan to keep his brother believing their clan was a noble one. Itachi had always planned to die by Sasuke's hands, so he could compensate for all he had done by making Sasuke's name known as the hero who defeated the one who slaughtered the Uchiha Clan. The reason why Itachi didn't kill Sasuke was because he felt a great love for him.
Abilities
In the few battles he has been seen in since the start of the series, Itachi was shown to be a very powerful ninja, and easily one of Akatsuki's strongest members. This is demonstrated by his ability to easily defeat
Deidara and
Kakashi Hatake. He is a master of the
Sharingan, as he has demonstrated great talent with its abilities, such as its unique genjutsu throughout the series. When faced with an opponent's Genjutsu, Itachi can use his Sharingan to dispel it or perform "Demonic Illusion: Mirror Heaven and Earth Change" (魔幻・鏡天地転,
Magen: Kyō Tenchi-ten) and turn the Genjutsu against its user.
[12] Itachi is also noted to be very fast with his movements, since Kakashi, a fellow Sharingan user, couldn't keep up with his speed.

Itachi's Mangekyo Sharingan with Tsukuyomi activated
Itachi also possesses the
Mangekyo Sharingan, which increases his already great power, and enables him to use his most powerful techniques. With his left eye, he can use
Tsukuyomi, a Genjutsu that traps an opponent's mind in an illusionary world, torturing them for what seems like days in a matter of seconds.With his right eye he can use
Amaterasu, a Ninjutsu which allows him to create a black flame that he can direct with his eyesight, burning everything in its path. His final technique is
Susanoo, a technique that manifests as a spectral being made of chakra resembling a yamabushi with a tengu mask surrounding his body. It wields the Totsuka Sword, a spectral sword with the ability to bind what it cuts into an alternate dimension, trapping it in a Genjutsu state forever, and Yata's Mirror, a shield that can reflect many attacks.
Zetsu, a fellow Akatsuki member, states that Itachi's mastery of the Sharingan's Eye Techniques and Genjutsu makes him invincible to many opponents.
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