Maa Kalaratri is the seventh Shakti of Maa Durga who is worshipped on the seventh day of Navratri pooja. This is the most violent form of Godess Durga. Kalaratri is the one of the fiercest forms of Durga and her appearance itself evokes fear. This form of Goddess is believed to be the destroyer of all demon entities. For the worshipers on this day door opens of every siddhi in universe.