Kaalaratri Devi is the destroyer of darkness within. She is an incarnation of Goddess Parvati and is said to have destroyed the demons Shumbha, Nishumbha, and Raktabeeja. She controls Lord Shani and also Sahastrachakra (the seventh chakra, situated in the head).
Her ride is a donkey, she is dark in complexion, and carries a sword and an iron hook. She controls the last milestone of human evolution, and is also known as Goddess Shubhankari. 
This episode was published during Navaratri by Chants of India Podcast, and has been narrated by Sriram. 
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