The story of the goddess Kali is told in the Devi Mahatmya of the Markandeya Purana.

The story of the goddess Kali is told in the Devi Mahatmya of the Markandeya Purana. She is an incarnation of Maa Durga. Maa Durga was created from the combined powers of Shri Brahma, Shri Vishnu, and Lord Shiva in order to defeat the demon Mahishasura. The incarnation of Kali happened after Durga's victory over Mahishasura. Once the demons Shumba and Nishumba defeated the gods in battle and took over the three worlds, so the gods went to mount Kailash to ask Maa Durga for help. After they said a prayer to Durga, Shiva's wife Parvati came by, and out of her body came a form of Durga known as Ambika or Kaushiki. During Ambika's battle with the Shumba and Nishumbha's Asura army, she was confronted by a pair of Asura generals named Chanda and Munda. To defeat them, Ambika created Kali out of her forehead, as described in Devi Mahatmya of the Markandeya Purana ;

"Thereupon Ambika became terribly angry with those foes, and her anger her countenance then became dark as ink. Out from the surface of her forehead, fierce with frown, issued suddenly Kali of terrible countenance, armed with a sword and noose. Bearing the strange skull-topped staff, decorated with a garland of skulls, clad in a tiger’s skin, very appalling owing to her emaciated flesh, with gaping mouth, fearful with her tongue lolling out, having deep-sunk reddish eyes and filling the regions of the sky with her roars, and falling upon impetuously and slaughtering the great asuras in that army, she devoured those hosts of the foes of the devas."

Kali defeated Chanda and Munda and brought Ambika their heads, for which she is known as Chamunda or Chamundeshwari. And she was instrumental in helping Ambika defeat Shumbha and Nishumbha and restore rule of the three worlds to Indra and the gods!! 💀👁💀

Jai Maa Kali Jai Maa Shakti 🕉🙏🕉