Kurma is the tortoise avatar of Vishnu that supports Mount Mandara during the churning of the ocean of milk.
In the Samudra Manthana story, the gods and asuras use Mount Mandara as a churning rod and the serpent Vasuki as the rope. The mountain begins sinking into the cosmic ocean, so Vishnu takes the form of Kurma and bears it on his back.
This avatar is the second of Vishnu’s commonly listed Dashavatara, following Matsya, the fish, and preceding Varaha, the boar. Different Hindu texts and regional traditions vary in how they list Vishnu’s incarnations, but Kurma’s role in supporting the mountain is consistent in the churning narrative.
Kurma is sometimes confused with Akupara, a cosmic turtle mentioned in other traditions. In this episode, however, the turtle is specifically Vishnu’s divine incarnation.