Duryodhan, the eldest Kaurava wanted to be king of Hastinapur when he grew up. He always looked for ways to harm his cousins, the Pandavas, who had equal rights to the throne. One day, with the help of his uncle Shakuni, he made a devious plan to kill Bhima, the strongest of the Pandavas. He invited the Pandavas to a picnic near the bank of river Ganga. He had poisoned some of the laddoos that were served. He offered these to Bhima who loved food. As soon as Bhima ate them, he fainted under the effect of the poison and Duryodhana pushed him into the river. In the river many poisonous snakes bit Bhima. It is said that 'poison kills poison.' The poison from the snakes cancelled  the effect of the poison from the laddoos. Bhima was saved; he swam to the surface and returned home.