Generally speaking, the reason for the formation of divine images is that the worshipped spirits gain self-consciousness and decide what they should look like; then, the divine image will turn into that appearance.
For example, the godmother of Huangyang Village is a God Demon Copper Statue, worshipped by the villagers long enough to have developed self-awareness, believing itself to be a fat person, hence the divine image has become that of a voracious fat person.
The godmother of Huangpo Village is an ancient tree, thinking it should be a young girl of eighteen or nineteen, so the divine image is that of a dignified and delicate young girl.
"The divine image will always be conscious, but the divine image in the Mountain Lord Temple has no consciousness, which means... the Mountain Lord is still alive!"