Susanoo

Susanoo is a technique that creates a spiritual being resembling a yamabushi. Itachi's version wields the sacred, a mirror that's considered one of the three sacred treasures capable of reflecting all attacks, as a shield in its left hand. In its right, the legendary, also known as the , is held. The Totsuka no Tsurugi, commonly sheathed in a sake jar held by a third hand growing from Susanoo's right forearm, is an ethereal weapon with an enchanted blade capable of sealing anything it pierces in an eternal dream-like illusion, and is described as the perfect counter to Orochimaru's Kusanagi Sword. Like the Amaterasu and Tsukuyomi, Susanoo is an ability of the Mangekyo Sharingan. Zetsu said that Susanoo's Totsuka Sword combined with the Yata mirror essentially makes Itachi invincible. Susanoo has been labeled as the "Raging God of Battle".

The Sword itself can be presumed as an extension added to the technique as Zetsu mentioned that no matter where Orochimaru searched for it, he could never find it. It is also possible the Mirror can be another extension, as Zetsu also mentioned that it is another legendary item, on par with the Sword.

Like the other Mangekyo Sharingan techniques, Susanoo comes with its own risks. To keep Susanoo sustained in the physical realm, the user must act as a medium for the deity, allowing it to consume their life force energy. This puts a severe strain on the user's body and prolonged use will lead to their death though this damage might have to do with Itachi's disease

Sasuke has also been shown to use Susanoo's bones to protect himself from the Current Raikage's Liger Bomb. Though Sasuke managed to survive the impact, one of Susanoo's rib bones snapped. Sasuke has also combined Susanoo with Amaterasu for defensive maneuvers, wrapping himself with the black flames of Amaterasu as a shield while protecting himself from it with Susanoo. Sasuke's version is slightly different in appearance, horns being the most noticeable difference as well as having a darker, evil looking aura surrounding it. It wields a blade in its left hand. Unlike Itachi, Sasuke has yet to show any strain on his own body for prolonged usage of Susanoo.

Influence

 * Similar to other Mangekyo Sharingan abilities, Susanoo was taken from Japanese mythology. Susanoo, the god of sea and storms, was the brother of Amaterasu and Tsukuyomi, with Susanoo born from Izanagi washing his nose.
 * The Totsuka Sword is the sword used by the god Susanoo to slay the eight-headed and eight-tailed snake, Yamata no Orochi, just like it was used by Itachi's Susanoo to defeat Orochimaru's.
 * The is one of the, together with the  and the Yasakani no Magatama (八尺瓊曲玉) Jewel necklace.
 * The is the sword used by Izanagi to kill his newborn son, Kagu-Tsuchi, after his birth burned his mother, Izanami, to death. From the blood of the Totsuka no Tsurugi, eight new Shinto gods were born.