King Ugrasena had a son named Kamsa and a daughter named Devaki. Devaki was married to Vasudaev. On the day of their wedding, Kamsa himself was driving his sister's chariot. A heavenly prophecy from the sky came and echoed, "Kamsa! Your end is near! The eighth son of Devaki, your sister, will be the one responsible for your death." Kamsa was enraged beyond control and imprisoned Devaki, his sister and Vasudeva her husband. Then he killed every child of the couple as they were born. But just the midnight when the eighth child was born, the skies roared and Lord Vishnu advised Vasudeva to take the child across the river Yamuna to the other side to the village of Gokul and exchange with the daughter of Yashoda in Gokul, who was born on the same day. Vasudeva accordingly put the child in a basket, and as he went out the doors of the prison parted for him as if in a magic. The river parted into two to allow for Vasudeva to cross. Vasudeva then crossed into Gokul and exchanged his son with the daughter of Yashoda who was born the same day and came back. The baby uttered cries which awakened Kamsa, and then happily he went to the prison chamber and snatched the girl baby and as he lifted her in the air, the baby, who was an incarnation of the Devi herself, laughed in glee "Kamsa, your real enemy is still alive. The son of Devaki is alive and well and will come back to kill you", and then disappeared. Kamsa was outraged beyond wits and started a killing spree of all boys at that age in his kingdom.
Krishna led a very pampered and amorous life in the Gokul, along side thousands of gopikaas, the cowherdesses who were all enthralled at his beauty and were thrilled whenever he played the flute. There are numerous playful instances of Krishna, playing mischief with the gopikaas including breaking their butter pots. Among all the gopikaas, one Radha was special to Krishna. Krishna is also known to be a very mischievous child who annoyed Yashoda a lot. A lot of dohas (poems) described by Mirabai, an ardent devotee of Krishna, are very popular which describe the naughty acts of Krishna. Among them the one titled "Maiya Mori Main nahi makhan khayo" is an all-time favorite. It describes the excuses which Krishna gives to his mother Yashoda explaining that he was not responsible for stealing of the butter from the gopikaas.
Krishna incarnated in this world to eliminate evil elements from this world. There are numerous tales of his bravery since his childhood. Many of the stories are related to the attempts by Kamsa, to kill Krishna after Kamsa came to know that Krishna was in Gokul alive. Some of the tales are given below
As Krishna grew older he left the heavenly Gokul, and the idyllic life alongside Gopis, to go and kill Kamsa. He killed Kamsa, and then settled in Dwaraka along with his brother Balram and learnt the traditional arts of fighting including archery. He arbitrated in the fight between the Pandavas and Kauravas in Mahabharata. During the war he is well known for his monologue to Arjuna on the battlefield, which is together termed as the Bhagvad Gita. There are many stories of Krishna, starting from his childhood to his death including his role in Mahabarata war, his rule over Dwaraka, his childhood acts with gopikaas including Radha, his winning of wives like Satyabhama etc.