Pinyin: tàn lédézh
Li: It refers to the ancient black dragon. Take the sphere under the dragon's jaw. It originally meant taking big risks and making big profits. Later, it was often compared to making a mountain out of a molehill, which caught the crux of the topic.
Idioms and their stories
Source: "Zhuangzi Lieyukou": "Take a stone and forge it. My husband's daughter's pearl must be in the nine abyss, under the dragon's chin, and the child who can get the pearl will sleep. You let the jackal fan the dragon. What's wrong with you? "