Bu Tian Ge (步天歌 Bù Tiān Gē), also known as Song of the Sky Pacers in English, is a manhua by Chinese artist, Xia Da.
The story follows the main heroine and protagonist, Chen Ating and her twin brother, the main hero and deuteragonist, Qu Chen. By cruel fate, the twins are separated after birth.
Qu Chen is taken into the spiritual world as a student under Cang Wuzi to train as a cultivator in Penglai as preparation for the coming Heavenly Calamity. Chen Ating is adopted by the lone swordsman, Chen Yansheng, but experiences tragedy after he is killed by the rogue cultivator, Baili Ji, who forces her upon the path of cultivation, and so, Chen Ating swears to take revenge.