Five million years ago, the ancient War God forged the Tianji Sword and sacrificed himself to seal the Ghost King of the Netherworld, with his disciples guarding it for generations. Due to a curse, none could draw the sword until ChuXiao—taken in by the Tianji Sect after his family's ruin—pulled it out during the Ghost King's assault on Yin Festival. With the possessed grandmaster defeated, the wounded predecessor named ChuXiao the new Heavenly Master.
