Blaze Release: Kagutsuchi

Sasuke Uchiha uses this technique to apply Shape Transformation to the inextinguishable black flames of Amaterasu, manipulating them at will. While Amaterasu is cast from Sasuke's left eye, he uses his right eye to manipulate the flames. After entering its final form, Sasuke's Susanoo gained an orb of black flames, which serves as an alternate source of flames for Sasuke to manipulate with this technique.

Variants
Sasuke shapes the flames of Amaterasu in different varieties, for both offence and defence.
 * While using the ribcage state of his Susanoo, Sasuke can create a defensive encampment by manipulating the flames to cover it. This can set ablaze anyone that attempts to engage him at close proximity, and thus be used to deter melee opponents.
 * Converging the flames in front of him, Sasuke can create a barrier of spike-shaped flames that not only shields him, but also burns and pierces any opponent that touches it.
 * Upon reaching its final stage, weapons can be manifested from the orb of black flames wielded by Sasuke's Susanoo. A sword, which he used to stab White Zetsu and slice through Kabuto's Spider Web Unrolling technique with relative ease, leaving black flames to burn away at what remained of both. Additionally, large arrows that can be fired from his Susanoo's bow that are powerful enough to damage the Ten-Tails once combined with Naruto's technique.
 * Sasuke is also shown to be able to wield the flames like a flexible sword in his own hand without being incinerated, as well as fire spike-shaped projectiles from the blade for a long-ranged attack.

Influence
Similar to other Mangekyō Sharingan abilities, Kagutsuchi's name is derived from Japanese myth and religion. Kagutsuchi is the God of Fire in Shinto and the one who brought death into the world by burning his mother Izanami to death as she gave birth to him. This made his father, Izanagi, kill him with the Totsuka sword.

Trivia

 * Although the sword version utilised by Susanoo is simply called "Blaze Release: Kagutsuchi" in the manga, in Naruto Shippūden: Ultimate Ninja Storm 3, it is named.
 * In chapter 585, the furigana of this technique's name were written in hiragana, not in katakana, as they're usually written.