Mangekyu Sharingan

A Mangekyō Sharingan is distinguished from a normal Sharingan by its appearance, which changes the form of the tomoe seal. The exact design differs for each user, though all resemble pinwheels. It is initially awakened by the trauma suffered from witnessing the death of someone close to the user. Uchiha,/b> 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 activated immediately after his trauma, whereas, in Naruto Jinraiden, Sasuke's Mangekyō didn't activate until several weeks afterwards.

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 awakens the Mangekyō in both eyes, or the ability of both of their eyes, they are able to perform Susanoo. In addition to the unique techniques, the straight tomoe of ,Madara's and Sasuke's Mangekyō Sharingan grants them fluidity in their movements when fighting.Madara was able to sense this form and later deduced that he and Sasuke must be connected by more than blood.