Shumbh and Nishumbh were sons of Danu. They wanted to avenge Mahishasura's death and sent many demons like to bring Goddess Chandika after enslaving her. First of all, Sugreev was sent followed by Dhumralochan but both of them were killed by the Goddess. When Shumbh and Nishumbh heard of their death, they were infuriated.
Nishumbh attacked the goddess with a huge army. Shumbh attacked from the other side. In the fierce battle, Goddess Chandika broke Nishumbh's sword as well as his shield. Nishumbh then attacked Goddess Chandika with his weapon- Shakti. Goddess Chandika broke it with her Chakra. At last, she attacked him with her arrows at him and as a result, Nishumbh got injured and fell.
Nishumbh attacked the goddess with a huge army. Shumbh attacked from the other side. In the fierce battle, Goddess Chandika broke Nishumbh's sword as well as his shield. Nishumbh then attacked Goddess Chandika with his weapon- Shakti. Goddess Chandika broke it with her Chakra. At last, she attacked him with her arrows at him and as a result, Nishumbh got injured and fell.
When Shumbh saw Nishumbh, injured and unconscious, he ran towards Goddess Chandika to kill her. Goddess Chandika blew her conch and made a thunderous noise by pulling the bowstring. Shumbh released the dangerous weapon- Ugradipti in the direction of Goddess Chandika. But her weapon Maholkanamni destroyed it. Shumbh thundered loudly and attacked Goddess Chandika with a volley of arrows but none could cause any harm to her. Finally, Goddess Chandika attacked Shumbh with her trident. Shumbh fell down unconscious.
After sometime, he regained his consciousness and attacked Goddess Chandika with his arrows. But she destroyed all the arrows. In the meantime, Nishumbh had regained his consciousness. He got up and attacked Goddess Chandika with his trident. In the end, Goddess Chandika killed Nishumbh by piercing her trident in his heart. As Nishumbh was dying, an another demon manifested from his body. Even he was killed by her. Her mount Simha devoured all the dead demons.