"The White Snake"
The Servant: The kind-hearted, nameless protagonist is a servant of a king. The king eats a strange dish every day, brought to him by the servant. One day curiosity gets the best of him and he eats a part of the dish - a white snake. This gave him the ability to hear animals speak. As he journeyed after being released (he had been wrongly accused of a crime, and his reward was freedom), he came upon three trios of creatures, and helped them each in turn. When he tried to win the hand of a princess by passing three tests, the animals helped him test by test, and he indeed won her hand and married her.
The Fish: These three fish were trapped in the reeds, and he put the fish back in the water, and they promised to help him. They later retrieved a golden ring for him, part of a series of tests to win a princess' hand.
The Ants: He avoided these ants so that he would not crush them, and they later helped him put all of the millet back in the bags, part of a series of tests to win a princess' hand.
The Birds: He killed his horse to feed these baby birds, thrown from their nest, and they later retrieved the golden apple from the tree of life, part of a series of tests to win a princess' hand.