Image from Moor.
Basic Description: Kurma, the 2nd avatar of Vishnu, helped the gods get the Nectar of Immortality by churning the Milk Ocean. Kurma bore the mountain on his back to allow them to churn the ocean without the mountain sinking into the ocean floor.
Mythology: During a battle between the asuras (demons) and gods (devotees of Vishnu) the gods were put under a curse and needed help. They prayed to Brahma who suggested that they get the Nectar of Immortality. He told them that there is a sacred ocean of milk that they needed to throw spices, grass, vegetables and other items in. Then they needed to churn the ocean and from this the Nectar of Immortality would come. In order to churn the ocean they would need to use the golden mountain, Mandara as the churning rod. As they tried to churn the ocean, the mountain sunk into the ocean floor. Vishnu then turned into a turtle and bore the mountain on his back. As they churned the water a deadly poison was produced which Lord Shiva drank to save the world. As they continued churning eventually the Nectar of Immortality was produced. Both groups wanted the nectar but Vishnu helped the gods get the Nectar. The demons then attacked the gods but with Vishnu’s help they defeated the demons.