Agasur was sent by Indra, the king of the Devas, to kill Krishna and his brother Balarama.
Indra, fearing the growing power of Krishna and his influence on the Yadavas, sought to eliminate them. He believed that Krishna's presence posed a threat to the Devas' dominion and sought to maintain their supremacy. He dispatched Agasur, a powerful demon, to kill the brothers, hoping to weaken the Yadavas and restore the Devas' dominance.
However, Krishna and Balarama, with their divine powers, outsmarted and defeated Agasur, showcasing their strength and divine nature. This victory further solidified their position as protectors of the Yadavas and strengthened their influence over the people.