There was once an evil asura named Bhima and he stayed in the dense forest of Dakini along with his mother Karkati. The Dakini forest was situated on the lofty ranges of the Sahyadri Mountains. Bhima had no compassion or kindness towards anyone or anything and even the divine and the mortal were afraid of this evil asura. But one thing which repeatedly tormented him was certain questions regarding his own existence. Bhima could handle the pressure anymore and one day he asked his mother about the mysteries of his life. He wanted to know who his father was and why the father was not with them. After much hesitation Karkati revealed that he was the son of Kumbhakarna and his younger brother was King Ravana of Lanka. Karkati told the story of Vishnu in his incarnation as Rama killed Kumbhakarna and Bhima was angry and vowed to take revenge on Lord Vishnu.
With this is mind, Bhima went on board on a severe penance to please Lord Brahma and Brahma granted him immense skills and prowess. After receiving the power to attack anyone, Bhima went on conquering everyone. He defeated Indra and conquered the heavens and he also defeated a staunch devotee of Lord Shiva, Kamarupeshwar. He was a nuisance to the rishies and sadhus and the Gods were angry. The Gods along with Brahma met Lord Shiva and Shiva told the Gods not to worry. In the meantime Bhima insisted that Kamarupeshwara, who was jailed, pray to him instead of Lord Shiva. Kamarupeshwara denied doing that and Bhima raised his sword to strike the Shiva Linga to which Kamarupeshawara was doing the puja. Lord Shiva appeared and the war began and after request from Sage Narada, Lord Shiva reduced the evil demon to ashes. The Gods and the sages gathered requested Shiva to make the place his holy abode and Lord Shiva manifested in the form of Bhimashankara Jyotirlingam. It is believed that the sweat that poured from Shiva’s body during the battle formed the Bhimarathi River.
