Kongōsōha

, or known as Adamant Barrage in English dub, is a special attack that launches shards of diamond (known by the more archaic term adamant in the Feudal era). The technique originally belonged to Hōsenki, who passed the technique on to the Tessaiga after its user Inuyasha proved his worth by choosing to save his friends over strengthening his sword.

The Kongōsōha is able to pierce the strongest barriers, including Naraku's barriers. The attack is not unbeatable, however, it is unable to pierce the armored shelled of Meiōjū. The Tessaiga can only use the technique by transforming into its diamond form.

Later in the manga the yōkai Mōryōmaru tricks Inuyasha into using the Kongōsōha on a Meiōjū (turtle yōkai) and then absorbs the yokai along with the diamond shards on its armored shell, thus giving him the ability to use the Kongōsōha. After Naraku absorbs Mōryōmaru he also gains the use of Kongōsōha and is able to add his shōki to the Kongosoha to make it more deadly.

Trivia

 * This technique cannot be used in the modern era, likely to prevent unlimited wealth.
 * In Urusei Yatsura: Kanketsuhen, the moment that Lum, Ataru, Rupa and Carla are pushed to the edge of high hills, Oyuki launched countless ice spears to block the way from falling from high place. The appearance of ice spears seemed similar like Inuyasha's Kongōsōha.