Mangekyō Sharingan

The is an advanced form of the Sharingan that has only been activated by a handful of Uchiha. They are noted to be the.

Overview
A Mangekyō Sharingan is distinguished from a normal Sharingan by its appearance, which changes the form of the tomoe seal. The exact design differs from user to user, though all resemble pinwheels. It is initially awakened by the trauma suffered from witnessing the death of someone close to the user. Uchiha have historically misunderstood this criteria as the user needing to be responsible for the person's death, and for that reason they developed the practice of killing their closest friends in order to gain the Mangekyō Sharingan. Obito's Mangekyō activate immediately after his trauma, whereas, in Naruto Jinraiden, Sasuke's Mangekyō don't activate until several weeks after the fact.

The Mangekyō Sharingan retains all of the Sharingan's generic abilities, such as casting genjutsu and the ability to distinguish chakra. In addition to these, the Mangekyō grants powerful abilities that differ from user to user, though abilities may be similar in nature; both Sasuke and Itachi have access to Amaterasu's flames, though the extent to which they can use them differ. The abilities of a Mangekyō Sharingan may not even be the same for both of a single user's eyes, as Itachi has Amaterasu in one eye and Tsukuyomi in another. Once a user unlocks the ability of both of their eyes, they are able to perform Susanoo.

The Mangekyō Sharingan's abilities drain a considerable amount of chakra when performed. Its usage and activity also place a great strain on the user themselves and over time deteriorates their vision until they are finally left blind. Their vision can be restored by receiving the transplanted Mangekyō of an Uchiha with strong blood ties — ideally a sibling — thus awakening so-called. The Eternal Mangekyō merge the designs of the transplanter and the transplantee's original Mangekyō. In addition to the unique techniques, there are apparently variants of the Eternal Mangekyō Sharingan, one being the, which seems to grant the user fluidity in their movements when fighting. Their Mangekyō-based abilities are made stronger and they no longer suffer any negative side-effects from the usage. According to Madara, the Eternal Mangekyō Sharingan is proof an Uchiha continues to seek something despite experiencing great losses.

As with any dōjutsu, Mangekyō Sharingan can be transplanted into non-Uchiha, granting them all its abilities albeit with steeper chakra demands. (In the case of eyes transplanted for the Eternal Mangekyō Sharingan, abilities are not transferred.) Abilities of a Mangekyō Sharingan can also be programmed to activate under certain circumstances, either within the user's own eyes or on a target of the user's choosing; this programming remains even after death.

Variations

 * Note: Sections are listed only for the original owners.

Itachi Uchiha
Itachi Uchiha awakened his Mangekyō Sharingan after the suicide of his best friend, Shisui Uchiha, shortly before the Uchiha Clan Downfall. With his left Mangekyō he can use Tsukuyomi, an extremely powerful genjutsu that allows him to distort the victim's perception of time. With his right Mangekyō he can use Amaterasu, creating inextinguishable black flames at the user's focal point that continue to burn until the target is reduced to ash. Because he has both of his Mangekyō abilities, he can use Susanoo. Use of the Mangekyō is particularly debilitating for Itachi, such that after using it three times in one day he can no longer keep even his normal Sharingan active. Despite this, he uses his Mangekyō enough that, at the time of his death, he is on the verge of complete blindness.

Itachi's eyes are transplanted into his brother, Sasuke Uchiha, after he dies.

Obito Uchiha
Obito Uchiha awakened his Mangekyō Sharingan after the death of Rin Nohara during the Third Shinobi World War; Obito himself only had his right eye at the time, but the event caused the Mangekyō to simultaneously awaken in Kakashi Hatake, who wielded Obito's left eye. Both eyes have access to Kamui, though the manner in which they can access it is different. The right eye is able to use close-range Kamui, allowing the user to teleport themselves or those they're is in contact with to Kamui's dimension. By teleporting only parts of their body there, they can in effect become impervious to damage. The left eye is able to use long-range Kamui, allowing the user to create a barrier around a target that teleports them to Kamui's dimension, though this requires precise aim. The left eye can also be used to teleport the user to and from Kamui's dimension.

Despite using his Mangekyō extensively for over a decade, Obito never experiences any deterioration of vision nor noticeable chakra loss. Kakashi, who only begins using his Mangekyō during Part II, is only able to use it a few times a day before requiring extended bed-rest and his vision eventually reaches the point where he can see very little with the eye. Regardless, his skill with the eye improves with time. When Obito and Kakashi are put into conflict during the Fourth Shinobi World War, they discover that each are impervious to each others' versions of Kamui.

Madara Uchiha steals Kakashi's eye in order to gain access to pursue Obito to Kamui's dimension. There, he exchanges the eye for Obito's Rinnegan, returning both eyes to their original owner. He uses them in combination effectively thereafter, but the eyes are destroyed when he is killed by Kaguya Ōtsutsuki's All-Killing Ash Bones. His spirit briefly returns to the living plane and inhabits Kakashi, giving him both Mangekyō's abilities and, by extension, Susanoo.

Madara Uchiha
Madara Uchiha was the first Uchiha to awaken the Mangekyō Sharingan, accomplished by killing his closest friend. His are the "straight tomoe" variety of Mangekyō, granting him superior movement-reading capabilities. It's not known what the individual abilities of each of his eyes were, but he was able to use Susanoo. Use of his Mangekyō during the Era of Warring States left him blind. This prompted his brother, Izuna Uchiha, to bequeath Madara his eyes on his death bed for the sake of preserving the Uchiha, thus granting Madara the Eternal Mangekyō Sharingan.

Towards the end of his life, Madara was able to evolve his eyes into Rinnegan, which he transplanted to Nagato before his death. The eyes eventually find their way back to Madara after he is revived.

Izuna Uchiha
Izuna Uchiha awakened his Mangekyō Sharingan shortly after Madara did. It's not known what the individual abilities of each of his eyes were. Before he died, Izuna left entrusted his eyes to Madara in order to restore his vision and thus protect the Uchiha from extinction. Despite Izuna giving the eyes willingly, Madara is popularly believed to have taken the eyes against Izuna's will.

Sasuke Uchiha
Sasuke Uchiha awakened his Mangekyō Sharingan after the death of his older brother, Itachi Uchiha, particularly his own role in Itachi's death. His are the "straight tomoe" variety of Mangekyō, granting him superior movement-reading capabilities. With his left Mangekyō he can cast Amaterasu. With his right Mangekyō he can shape the flames or extinguish them. He also tends to use genjutsu with his right Mangekyō, though it is not Tsukuyomi. Because he has both of his Mangekyō abilities, he can use Susanoo. Sasuke is initially reluctant to transplant Itachi's eyes and gain the Eternal Mangekyō Sharingan, claiming that his views were different from Itachi's. After he starts to experience a loss of vision he changes his mind, deciding he needs the increase of strength in order to kill Naruto Uzumaki.

Shisui Uchiha
Shisui Uchiha awakened his Mangekyō Sharingan through unknown means. With each of his eyes he could use Kotoamatsukami, a powerful genjutsu that allowed him to manipulate an opponent's thoughts completely without them having the slightest idea that they were being controlled. The only drawback of Kotoamatsukami was the fact that it couldn't be used again in a single eye until after a prolonged period of time. In the Ninja Escapades special included with Ultimate Ninja Storm Revolution, Shisui Uchiha could use Susanoo.

When Shisui attempted to use Kotoamatsukami in order to avert the Uchiha Clan Downfall, his right Mangekyō was stolen by Danzō Shimura, who felt Shisui was about to waste the eye's ability. Fearful that Danzō would take his other eye too, Shisui entrusted it to his best friend, Itachi Uchiha, and begged him to use it to save Konoha. Danzō transplants the eye he took into himself and uses it over the years to manipulate others to his way of thinking, drawing on the power of Hashirama Senju to reduce its recharge time. Danzō destroys the eye before his death so that nobody else could have it. Itachi transplanted the eye he was given into a crow that he planned to use to re-ally his brother, Sasuke, with Konoha. He ends up using it on himself instead when he is reincarnated in order to break free of Kabuto Yakushi's control. Itachi incinerates the crow afterwards so that nobody else could have the eye.

Indra Ōtsutsuki
Indra Ōtsutsuki was the originator of the Sharingan and by extension the Mangekyō Sharingan. It's not known what the individual abilities of each of his eyes were, but he was able to use Susanoo.

Shin Uchiha
Shin Uchiha awakened his Mangekyō Sharingan through unknown means. It's not known what the individual abilities of each of his eyes are.

Designs

 * Mangekyō Sharingan

Trivia

 * Originally in the anime, Itachi Uchiha was shown using techniques exclusive to the Mangekyō Sharingan without having it active. This is because Kishimoto had not revealed the appearance of the Mangekyō Sharingan in the manga yet. A true form of the Mangekyō Sharingan was first seen, from Itachi, while Sasuke remembered the events leading to the Uchiha Clan Downfall as he fought with Naruto Uzumaki at the Valley of the End.
 * The manners in which an individual gains the Mangekyō Sharingan are almost parallel to how an Uchiha awakens their regular Sharingan for the first time, since both need intense emotions to awaken them.