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Within the box was a jade token, entirely black in color.
Zhou Yu reached out and touched it, and in the next moment, a look of surprise and delight appeared in his eyes.
"Such pure Yin Soul Force!"
"I didn't expect the Ghost Talisman Elder to have such a thing. It seems he planned to use this to condense his Primordial Spirit."
One must know that in the path of Qi Refinement, after achieving the transformation from Qi to spirit, one could reach the Innate realm.
To breakthrough the Innate realm and transcend into sainthood, one must cultivate a Primordial Spirit.
The Primordial Spirit is divided into the Yin Spirit and the Yang Spirit.
Generally speaking, Qi Refinement martial artists cultivate the Yin Spirit, while Body Refinement martial artists cultivate the Yang Spirit.
And the Yin Soul Force is an essential element for cultivating the Yin Spirit.