The three organs that Wang Wei tempered with and absorbed the necessary material are: the liver, kidney, and lung. As for the materials needed, they are based on the five elements.
The lung represents metal, the kidney stands for water, and the liver for wood. According to the Five Elements theory, metal (lung) promotes water (kidney), water promotes wood (liver).
The process will continue until a cycle of promoting and restraining occur to achieve a state of balance. Unfortunately, Wang Wei does not have the remaining two materials yet; the reason being that his requirements or the sect's requirements were very high.
In order to give Wang Wei the best possible advantage, the Dao Opening Sect chose Innate Treasures of Heaven and Earth to allow him to refine his fleshly body.
Innate treasures are a very special type or quality of material. In some ways, they are even more powerful and rare than Emperor level materials.
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