In the variation, Lord Vishnu knew that Vasuki would vomit poisonous flames when twisted and pulled, and therefore advised the Devas to hold the tail end of the snake, without telling them the reason. First, the Devas held the head end of the snake, while the Asuras held the tail end. The Asuras were enraged by this, as the lower part of an animal is impure, or less pure, than the part that contains the head. They insisted on holding the head side of the snake. Lord Vishnu had an inkling that his reverse psychology would work. The Asuras demanded to hold the head of the snake, while the Devas, taking advice from Lord Vishnu, agreed to hold its tail. When the mountain was placed in the ocean, it began to sink. Vishnu, in the form of Kurma (lit. turtle), came to their rescue and supported the mountain on his shell. The Asuras were poisoned by fumes emitted by Vasuki. Despite this, the Devas and the Asuras pulled back and forth on the snake's body alternately, causing the mountain to rotate, which in turn churned the ocean.