Yin and Ning, siblings bound by blood, have roamed the countryside together ever since their hometown fell to the malevolent Taibai Empire, traversing treacherous forests and abandoned villages. Their childhood companion, Zhao, now serves as a captive under Taibai himself, employing his knack for tinkering and invention to survive the Empire's caprices while its iron grip tightens. On a fateful day, Yin stumbles upon an ancient blade that bestows extraordinary combat prowess and summons a mystical mechanical fox spirit, Yun, pledged to stand beside her, while the wind carries whispers of ancient legends. At the same time, Zhao quickly befriends a enigmatic youth who may harbor immense power inside the Taibai ranks, her presence both enigmatic and intimidating. As Zhao and the Fu sisters become more entangled in the Empire's struggle for dominion, only the combined magic and strength of emerging rebel forces can finally reverse the war's course as the Empire's iron fist threatens all who oppose it.