|“||Jade-edged Glaive obtained upon the defeat of Ninetails.||”|
— in-game description
The Blade of Kusanagi (「草薙剣」?; Kusanagi no Tsurugi) is the third Glaive to be obtained by Amaterasu in Ōkami. It is also the third most powerful, after the Thunder Edge and Eighth Wonder. It is depicted as a jade green-colored glaive with the handle and blade separated at the guard, and a wind pattern flowing through the circular gap.
- The Blade of Kusanagi is one of the three Imperial Regalia of Japan. In real legend, it is the sword used by Susanoo Omikoto to slay Yamata no Orochi.
- Tsumugari is found the same way the Blade of Kusanagi was obtained by Susanoo. This reflects the relationship between the two swords, as Tsumugari is another name for the Blade of Kusanagi.
- Another name for Kusanagi is Ama no Murakumo, which appear later in the game as the Thunder Edge glaive in English version.
- Kusanagi no Tsurugi means Grass Cutting Sword in Japanese. However in ancient Japanese it translates into Snake-Sword.
- The Grass Cutting Sword name meaning is reflected in the game when Amaterasu charges up the glaive and hit the enemy. What appears to be small, shining blades of grass appear when it was done (if observed closely).
- Concept art of Glaives shows that original version of Blade of Kusanagi apparently wields ability to control and cast winds based on the description which says a "tornado" surrounds the blade.