What is "mahishasura"

According to Hindu mythology, Mahishasura was a combination of both an Asura and a Mahisha ( aurochs) with trident. He intended to annihilate all the Devas since they were the arch-enemies of Asuras. The legend of Mahishasura is important in Hindu mythology since the goddess Durga was born in order to slay him. Therefore, his story is an important part of shaktiism which venerates the goddess Durga.