Shukdev ji tells a story of elephant Gajendra Moksha to Raja Prakshit. On Trikuta Mountain, one strong and powerful elephant named as Gajendra lived. He was husband of many female elephants. It was very hot summer. Gajendra along with female elephants & children went to a lake for playing in water. The elephants began to splash water on one another.
Suddenly, a crocodile named as Magara caught one leg of Gajendra. Gajendra tried hard to get rid of him but could not break free. Elephant is terrestrial animal and Magara is aquatic animal. Terrestrial animals become weak in water. He then, called out for help. All elephants gathered around him and tried to help, but in vain. Magara was pulling the Gajendra into deep water. The struggle between Gajendra and Magara continued for one month. Other elephants thought that Gajendra would not survive and hence, they left from there.
Gajendra was began to tire and believed that nobody would help him. He realized that only almighty could help him. Gajendra desperately called up Narayana for help. Hearing the call of Gajendra, Vishnu Bhagwan appeared on his vehicle Garuda. Gajendra saw Vishnu Ji and offered one lotus flower. Vishnu ji accepted lotus flower and killed Magara with his sudarshan chakra.
Shrimad Bhagwat Mahapuran by Shri Ramchandra Keshav Dongra ji Maharaj