The name "Ame no Murakumo" is derived from the legendary Kusanagi-no-Tsurugi sword of Japanese folklore. It was once known as Ame-no-Murakumo-no-Tsurugi (Tian Cong Yun Jian). The word "Kusanagi" means "moon blade" and "Tsurugi" means "nine tails". Combined, they mean "moon blade that cuts through nine layers of armor". This sword is said to have been owned by a goddess who took human form in order to protect people. This goddess was called "Amaterasu" after her tribe. She is considered one of the eight mighty gods of Japan. In anime, manga, and video games, Murakumo usually serves as a weapon wielded by characters who are based on myths or legends. It has also been used in fictional stories where other swords are preferred. The character with the sword often plays an important role in the narrative. There are many versions of how Murumuru came into existence. According to one version, a samurai named Kurokawa Hideyoshi wanted to create a sword that could never be defeated so he ordered his sword maker to craft him a tool that would always win. The sword maker agreed, but instead of making just one sword, he made three very powerful ones. Then he gave one of the swords to Hideyoshi as a gift.