Krishna and Kaliya Naag
कृष्ण
The Yamuna River flowed through Vrindavan, and everyone depended on it for drinking and bathing. One day, a massive poisonous serpent named Kaliya came to live in the Yamuna. His venom turned the water black and toxic. Any bird or animal that went near the water died. The villagers were terrified and helpless. One day, Krishna was playing with his friends near the riverbank. Their ball fell into the water. Without any fear, Krishna jumped into the Yamuna. The giant serpent Kaliya wrapped Krishna in his coils. Everyone on the shore screamed in panic. But Krishna expanded his body so much that Kaliya's grip loosened. Krishna climbed onto Kaliya's many hoods and began to dance. With every step, Kaliya grew weaker and weaker. Finally, the great serpent surrendered. Kaliya's wives begged Krishna for mercy. Kind-hearted Krishna forgave Kaliya and told him to leave the Yamuna and go live in the ocean instead. Kaliya departed, and the waters of the Yamuna became clean and pure once again.
Moral
Face evil with courage, but always show mercy.