He defeated a great deal of gods from heaven to earth and ruined this planet. All gods did prayer to lord Brahma to avoid wasting their life which planet from demon Mahishasur and his risk. Also gods were worry to combat with Mahishasur and his army. Inside the Srimad Bhagavatam, https://geoffreyf184mlm0.daneblogger.com/30393435/a-simple-key-for-durga-unveiled