Third season of .

The anime series is set in the future when humanity migrated to the Moon due to Earth's climate change. It will incorporate original elements unique to the anime, such as human drama about survival, and will feature a diverse field that blurs countries and eras such as Shibuya, the Edo-period era, and London.

One hundred years ago, in the battle of Mirage Land, the fairy Tianjuan killed the Lord of Mirage with her own hands. However, Tianjuan's soul was incomplete and she lost her memory of the war. After the war, Tianjuan came down to earth and to serve as the landowner in Cangshuo. She adopted the fairy pet Li Xiao, which looked like a little black bird. Then the war goddess and the little black bird teamed up to solve a case. Behind a series of strange murders, they found traces of the mirage monster returning to the land of Cangshuo! As Li Xiao transforms, Tianjuan discovers that there is a possible connection between her dead lover Shao Weili, Li Xiao, and the Lord of Mirage whom she killed...

The top of the immortals, proud of the world, as long as my ancestor An is there, there is the sky. There are three million sword immortals in the world, and they must bow their heads when they meet me. As a sword immortal, I should suppress all enemies in the world. Who claims to be invincible, who claims to be undefeated?