About 5000+ years ago tere was an epic war which lasted for decades which means the suffering of common civilians also lasted for long... Evil powers were ruling the earth. But Avatar of great god vishnu established the peace in the world. After that there was dangerous weapon called "Dhansang " Before going to after life Avatar Krishna told King parikshita to dismantle that weapon and divide its power into places.
King parikshita tried to dismantle it but it was divided in just two parts which was way too dangerous to let that weapon be.
So parikshita made team of worthy people on whom he had his faith.He called them Ananjam.There were only four people and King parikshita distributed the power of Dhansang to them. But the weapon had too much power that normal mortal can't bear that power.. One of the Ananjam the Harsha Distributed that power in Environment and that power formed mystical animals. About 6 Mystical animals formed by that energy. Those animals could talk to human, then Parikshita told those animals to go in different parts of world to maintain the balance of eternal energy.
AFTER THAT PARIKSHITA LEFT THE WORLD AND GONE TO AFTER LIFE...