Yinling, in fact, is also hierarchical.

They are graded according to how much resentment has accumulated. And resentment, each to a certain amount, will occur on the color change.

Before that, the ancestors of Taoism summed up the experience of many people and finally made a detailed classification.

There are six kinds in total, each of which corresponds to a color. The reaction of color shows the accumulation of resentment and the influence of Yin spirit on human illusion. The more powerful the spirit is, the more intense the color will be in human eyes.

In the picture