There were two main ingredients in the secret medicine needed to advance the Formless Art to upper seventh-rank: the crest of the divine bird Nine-Phoenix and the heart of the demonic serpent Xiangliu.
In legend, Nine-Phoenix was a type of phoenix. Other tales claimed it had been formed when an ancient sovereign merged with his nine consorts.
The Classic of Mountains and Seas said that in the great mountains of the far north lived a nine-headed phoenix with human faces and a bird's body, named Nine-Phoenix.
Nine-Phoenix's crest consisted of the nine fleshy combs on its heads.
Xiangliu was also a divine beast, with a serpent's body and nine heads. It devoured countless humans throughout its life, and wherever it went became a watery kingdom.
Nine-Phoenix commanded nine different yang powers, while Xiangliu commanded nine different yin powers.
Since Xiangliu was one tier below Nine-Phoenix, this secret medicine required only Nine-Phoenix's crests but needed Xiangliu's heart.
With these, the Formless Art could advance to the seventh layer, raising one's Origin Power cultivation to upper seventh-rank.
Naturally, a seventh-rank martial cultivator could not obtain a true Nine-Phoenix's crests or a true Xiangliu's heart.
The secret medicine only required distant bloodline descendants of Nine-Phoenix and Xiangliu at upper seventh-rank.
If even those could not be found, the requirements could be lowered further, but the Formless Art they cultivated would then no longer offer a path straight to first-rank.
This showed why humans and demons were mortal enemies, forever guarding against one another.
Advancement in many Human Race cultivation arts required parts of demons' bodies as ingredients. The same held true for demons: Human Race blood was said to brim with spirituality because of the bloodline seal, making it an excellent ingredient for increasing the purity of demonic bloodlines.
Rumor also held that