Kaze no Kizu

The also known as the Wind Scar, was a special technique and the signature attack of the Yōkai sword Tessaiga, currently wielded by Inuyasha.

This attack is accomplished by finding the rift, or scar, between two powerful yōkai auras of Tessaiga's wielder and the opposing yōkai. Once the rift is found, the wielder of Tessaiga can swing the sword into the rift, releasing a powerful energy wave that has the power to kill 100 yōkai in a single sweep.

Although Inuyasha came into the possession of the Tessaiga, ironically it was actually Sesshōmaru who used the technique first, even though it was his first time using the sword: a testament to his natural intelligence and skill as a swordsman. Not only did Sesshōmaru use it intentionally, but he also knew what it was, likely from observing his father use it.

Inuyasha used the Kaze no Kizu for the first time unintentionally when he was trying to save Miroku so he wouldn't use his Kazaana. When the wielder becomes proficient enough, the Kaze no Kizu surrounds Tessaiga when the wielded puts their own yōki into it.

Built upon this attack is the more powerful attack called Bakuryūha. Inuyasha first used Bakuryūha while he was fighting Ryūkotsusei, the demon that Inuyasha's father sealed away. Inuyasha, again accidentally, used Bakuryūha when he tried to use Kaze no Kizu. Defeating Ryūkotsusei resulted in Inuyasha's mastering of the Kaze no Kizu and Bakuryūha, thus making Kaze no Kizu usable even without considering the yōkai aura.

The Kaze no Kizu can only be performed if one uses the Tessaiga. The only exceptions are in stealing Tessaiga's power and absorbing it into one's own sword, as with Kanna's Mirror Demon, Ryūjin's shield, as well as the demon sword Dakki, which was wielded by a swordsmith named Tōshū.

Sometimes Kaze no Kizu produces a high pitch sound 1~2 second(s) after it is launched. (Especially when there's no background music playing.) One example is in the Movie 4 when Inuyasha fired the Kaze no Kizu at Ryūra, before launching the Kongōsōha.

Trivia
Kaze no Kizu Viento cortante Kaze no Kizu Phong Thương 风之伤
 * Although this attack is used to protect humans and destroy demons, Toga used them in the third film to destroy the walls of Izayoi's Castle, but some humans were also killed.