Durga Puja celebrates the victory of the goddess Durga over the demon king Mahishasura. It begins on the same day as Navratri,
Agamani (Bengali: আগমনী গান Āgōmōni gān "Songs of advent") and Vijaya (বিজয়া গীতি Bījōyā gīţi "Songs of parting")
Mahishasura was the son of Mahisi (Buffalo) and the great-grandson of Brahmarshi Kashyapa. He was ultimately killed by Goddess Durga by her Trishula (trident) after which she gained the epithet Mahishasuramardini ("Slayer of Mahishasura").
