Kalratri is the long dark night during total annihilation or Mahapralaya. As per Markandeya Purana, at the end of a kalpa (end of one cycle of creation), Lord Vishnu is fast asleep. She is that form of Goddess Durga, which sucks up all creation. What then remains is total darkness. The entire energy in the universe is sucked up by Kalaratri. Brahma appears on a lotus that sprouts from the navel of Vishnu. Brahma contemplates about creation but suddenly two demons, Madhu and Kaitabha, who had grown from Vishnu’s earwax stood before him with mouths wide open to gulp him. Lord Brahma tries to wake up Vishnu but is not successful. Yoga Nidra (goddess of sleep) had taken hold of his eyes. Brahma then performs intense austerities. He invokes Yoga Nidra by three names – Kalaratri, Maharatri and Moharatri. Yoga Nidra then withdraws from the eyes of Vishnu. Srihari Vishnu then annihilates the demons. Mahapralaya, or the total annihilation of the universe after a cycle of cre