By Swami Harshananda
Kālayavana was a very powerful warrior and demoniacal in nature. He harassed the Yādavas many times and even attacked their capital Dvārakā.
During one of his attack on Dvārakā, Kṛṣṇa tactfully drew him away and ran into a dark mountain cave where the great king Mucukunda was sleeping and hid himself. Kālayavana entered the cave and kicked the king thinking that he was Kṛṣṇa. When the king opened his eyes and saw Kālayavana, the latter was immediately reduced to ashes. King Mucukunda was granted this boon from the gods whom he had helped them in their fight against the demons.
- The Concise Encyclopedia of Hinduism, Swami Harshananda, Ram Krishna Math, Bangalore