The Prologue introduces Yang Guang, the ace pilot of the Nine-Tailed Fox as he battles a group of Hunduns to protect Huaxia. The Nine-Tailed Fox is a gargantuan mecha-fox made out of the metallic corpses of the alien invader Hunduns. The mechas such as the Nine-Tailed Fox are called Chrysalises and are piloted by a duo of pilots, always one boy and one girl. The boy sits in the yang seat and the girl sits in the lower yin seat. Guang uses his qi to pilot the Chrysalis, a magical force that is inherent in everything. Qi comes in five varieties: Earth, Wood, Water, Fire, and Metal, each with its own distinctive traits, advantages, and weaknesses to one another. A pilot’s qi type determines the typing of their Chrysalis, mirroring the strengths and weaknesses of the qi itself.

Yang Guang fights beside the pilot of the Xing Tian Chrysalis, a legendary headless warrior of Chinese mythology with a face on his chest and abdomen. As Yang Guang tears through the Hunduns, he experiences their emotions when the Chrysalis makes contact with the Hunduns. A prince-class Hundun, one larger and more powerful than the common classes, appears in the fray. Such a powerful Hundun, if killed cleanly, can be turned into a prince-class Chrysalis or otherwise offered up to the gods.