Tsumukari Muramasa.
A Noble Phantasm that creates the ultimate sword. After deploying a unique Reality Marble, a wasteland of countless swords similar to the Heroic Spirit Emiya's Unlimited Blade Works, all the swords shatter and scatter like snow crystals to reveal a single blade in Senji Muramasa's hands. A single slash of this cuts time, space, and even fate.
"Every path, every desire, every injustice... All of it has been for this single swing."
The blade's name: Tsumukari Muramasa. The term Tsumukari refers to Tsumukari-no-Tachi, the sacred sword of Ama-no-Murakumo/Kusanagi that emerged from the tail of Japan's greatest serpent and calamity, the monster with red eyes, eight heads and a length spanning eight valleys called Yamata-no-Orochi, which was killed by Susanoo-no-Mikoto.
According to one theory, "kusa (草)" is a word that indicates a degree of origin[3] and "zo (雑)" is a word related to cutting, which together give Kusanagi the meaning of "a sword that can cut well and frighteningly". (Another theory gives it the meaning of "sword that came out of a snake," since Kusa means odor and Nagi means a snake.)
Generally speaking, it is said that the name of the sword "Kusanagi" is a name linked to the later Yamato Takeru[4] legend. However, Motoori Norinaga says in the Kojikiden that the sword was actually called the Kusanagi sword from the moment Susanoo took it in his hand[5]
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