The story of Sahasra Kavacha Rakshasa - The Thousand Armoured One

We all know that Karna, son of Kunti was born with a natural armour and ear rings.
Karna, in his previous birth was a Rakshasa. As is wont with the Rakshasas, this Rakshasa also
wanted to be invincible. With that end in mind, the Rakshasa prayed Brahma for a long time. Brahma was pleased and appeared before him and offered a boon.





Now the Rakshasa knew total invincibility would not be granted so instead he asked for this boon.

The boon was, the Rakshasa would get a thousand armours on his body "naturally" and if one were to kill the Rakshasa, one would have to meditate for a thousand years and then fight with the Rakshasa for another thousand years and the Rakshasa would lose one armour, thus only after losing all the armours would he be killed. Brahma granted the boon.

The Rakshasa after gaining this boon became arrogant and started creating trouble. Now it fell to the part of Lord Vishnu to vanquish the Rakshasa.

Meanwhile another demon Hiranya Kasipa was creating havoc and his end was near. So Lord Vishnu had to don the avatara of Narasimha and kill him. After killing Hiranya Kasipa Lord Narasimha's head portion became Narayana and the body portion became Nara as part of the plan to vanquish the thousand armoured Rakshasa.

Now while Narayana was meditating, Nara would fight the Rakshasa for a thousand years and make him lose one armour and immediately afterwards Narayana would get up and fight the Rakshasa while Nara sat down to meditate. Thus they would take turns to fight the Rakshasa relentlessly. After losing all but one armour, the Rakshasa feared his end was near and prayed to Sun God for his safety. Sun God took pity on him and promised to help him.

At about the same time this was happening, Kunthi Devi, had recieved a mantra from the great rushi, Durvasa. According to Durvasa, if Kunthi were to have a particular deity in mind and chant the mantra, that deity would appear in front of her and give her whatever she desired.

Kunthi, desirous of testing the mantra, thought of Son God and chanted the mantra, lo and behold, Son God indeed appeared in front of her in all his splendour. Kunthi was awestruck at the brilliance and majestic appearance of Sun God and involuntarily thought, how wonderful it would be if she could have a son like that. She had forgotten that the mantra would grant whatever she desired. Since she desired a son, Son God said so be it and placed in her hands a brilliant boy with a natural armour and ear rings and vanished. This boy was none other than the thousand armoured Rakshasa, whom the Sun God had promised safety.
In this birth, the boy was known as Karna.

Nara and Narayana were surprised at the sudden disapperance of the Rakshasa. Narayana through this yogic power could figure out all that had happened and decided that they, Narayana and Nara would also take birth as Krishna and Arjuna and vanquish Karna. Atlast in the battle field of Kurukshetra, Arjuna kills Karna. Thus Narayana and Nara put an end to the Shasrakavacha Rakshasa.