

The form of Durga was created as a warrior goddess to fight the demon mahisasura. Mahishasura had the boon that he could not be defeated by any man or god. He unleashed a reign of terror on earth, heaven and the nether worlds with his newly found powers.
Eventually, since only a woman could kill him, the trinity bestowed a dazzling beam of energy upon the Goddess Trinity of valour, wealth and knowledge - transforming them into the goddess, Durga.
Navarathri marks the 9 days of war where on the tenth day of the waxing moon, goddess Durga killed the demon Mahishasura with her trident.