Skanda Purana says that Kalanemi was even more powerful than Mahishasura and all the Asuras killed by Adi shakti
O Janardana, well done! well done! There is no one else to do what has been done by you. This Daitya is stronger and far more powerful than the demons, very difficult to be conquered, beginning with Mahisa and others—those demons who were struck down by the Goddess. He has been defeated by you.
- Chapter 32, Kaumarika Khanda, Skanda Purana.
Kalanemi crushed all the devas led by Indra in battle
In the battle, the gods were terrorized by Kalanemi. Though they tried, they were bereft of their senses and were incapable of making efforts. In the battle, he used arrows to bind down Shakra, the thousand eyed one, while he was astride Airavata and he was incapable of moving. In the encounter, he deprived Varuna of his noose and repulsed him in every way, so that he looked like a cloud without any water or an ocean without any water. Vaishravana could assume any form at will and fought with clubs. However, the lord of riches was defeated, prevented from acting and lost his guardianship of the worlds. Yama is the one who takes everything away and uses death as a weapon. However, that immortal was deprived of all of Yama’s powers and fled to his own direction. He appropriated the tasks of the guardians of the worlds and dividing his body into four parts, took over the four directions. With Svarbhanu indicating the way, he went to the the divine path followed by the nakshatras. He seized Lakshmi (prosperity) from Soma and deprived him of his great kingdom. The sun, the one with the blazing rays, moves along the gate of heaven. However, he seized his kingdom, the solar paths and the task of determining times of the day. Agni is the mouth of the gods. On seeing him, he replaced Agni’s mouth with his own. He swiftly defeated Vayu and brought him under his own subjugation. He forcibly brought the ocean and all the rivers under his control. Through his energy, he controlled all the bodies of water and made them part of his own body. He conquered all the waters, whether they were on heaven or on earth, including those that were protected well by the mountains. It was as if he established his own universe.
- 37, Harivamsa, Mahabharata, CE.
Kalanemi then rushed to attack Lord Vishnu. But Lord Vishnu with the great chakra destroyed the demon. Garuda threw down the demons body on the ground
Blazing with rage, Gadadhara raised this chakra in the battle. With his own energy, Shridhara dried up the danava’s energy in the battle. With the chakra, he severed Kalanemi’s arms. The daitya possessed one hundred curved and terrible heads that seemed to spit fire and laugh out aloud. Using his force and strength, Hari severed these with his chakra. Though his arms and heads were severed, the danava did not waver. The headless torso remained in the battle, like a tree bereft of its branches. Garuda stretched out his giant wings and his speed was like that of a storm. He struck Kalanemi with his chest and brought him down. Deprived of a head, the body whirled around in the sky and fell down. Dislodged from the firmament, it fell down and agitated the surface of the ground. When the daitya fell down, the gods and large numbers of rishis pronounced words of praise and collectively worshipped Vaikuntha.
- 38, Harivamsa, Mahabharata, CE.