Lu Chen, a humble medicine apprentice of Qingyun Sect, relies on the "Reason-Analyzing and Medicine-Distinguishing Method" to extract medicine marrow from waste dregs, reconstructs medicinal properties with cold spring sand, and refines top-grade Guyuan Powder. The Pei family monopolizes red marrow to participate in Huaying Pills, forcing outer and inner disciples to beg for medicine at high prices. However, Lu Chen uses wild cold grass, green vines, and slag to rebuild the five-element pharmacology, successively launching Shuanghua Powder and non-toxic new Huaying Pills. After the Mingtang Dan Discussion, he wins the Dan Pavilion's medicine-master seal, abolishes hereditary rations and recipe blockades, and compiles the "Dan Canon of Reason Analysis", enabling humble-born cultivators to pursue the Dao through pharmacology. In the end, the furnace fires shine brightly once more, the old alchemy iron curtain is thoroughly overthrown, and a new path of seeking truth starts from here.