Muchukunda

Muchukunda, son of King Mandhata, and brother of equally illustrious Ambarisha was born in the Ikshvaku dynasty. Ikshvaku dynasty is also known as Suryavamsha. The important kings of this dynasty are Harishchandra, Dileepa, Raghu and Sri Rama.

Once, in a battle, the deities were defeated by the asuras. Tormented by arrows, they sought help from king Muchukunda. King Muchukunda agreed to help them and fought against the asuras for a long time. Since the deities did not have an able commander, king Muchukunda protected them against the onslaught by asuras, until the deities got an able commander like Kartikeya, the son of Lord Shiva. Then Indra said to the king Muchukunda, "O king, we, the deities are indebted to you for the help and protection which you have given us, by sacrificing your own family life. Here in the heaven, one year equals three hundred and sixty years of the earth (relatively). Since, it has been a long time, there is no sign of your kingdom and family because it has been destroyed with the passage of time. We are happy and pleased with you, so ask for any boon except Moksha (liberation) because Moksha (liberation) is beyond our capacities".

Muchkunda asks Indra for a boon to sleep. While fighting on the side of the deities, King Muchukunda did not get an opportunity to sleep even for a moment. Now, since his responsibilities were over, overcome by tiredness, he was feeling very sleepy. So, he said, "O King of the deities, I want to sleep. Anyone who dares to disturb my sleep should get burnt to ashes immediately".

Indra said, "So be it, go to the earth and enjoy your sleep, one who awakens you would be reduced to ashes".

After this, King Muchukunda descended to earth and selected a cave on a hill [some locate this to mount Girnar ], where he could sleep without being disturbed.

Kalayavan, the great Yavana warrior king, was killed by Muchukunda's gaze in the Indian epic Mahābhārata.

Kalayavan was undefeated and unmatched in battle due to a boon, but he was also merciless and cruel. He learns that Krishna is the only person who can defeat him in battle and accepting this challenge sets out to invade Krishna's kingdom, Mathura. When the two armies faced each other in battle, Krishna dismounts from his chariot and starts walking away, followed by Kalayavan. After a long time Krishna, followed by Kalayavan, enters a dark cave. In this cave Muchukunda was sleeping since the time he was blessed by king of deities.

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Wikipedia