The Millennium Ginseng is the only thing Ye Tianchen could think of to cure Hu Gao. On Earth, there's no Life-extending Elixir available. Only this Ten Thousand Year Old Ginseng remained, and it escaped from the tomb of the Purple Bamboo Great Saint despite being besieged by two formidable foes, Wuji Taoist and Golden Elder. This showed the spiritual nature of the divine medicine, which was not easily found.
By a twist of fate, or perhaps by the destiny written in the stars, Ye Tianchen searched tirelessly for three days and nights but could not find any trace of the Millennium Ginseng. It was only during a moment of venting his anger that he accidentally dropped the "Dragon Crystal," which resonated with a nearby Dragon Vein. To Ye Tianchen's surprise, the Millennium Ginseng was found residing within this Dragon Vein.