Surasa

Hanumana began increasing his size. He became ten yojanas tall. Wanting to grow further, he doubled his size. The mountain on which they were standing started swaying .Hanumana took his position. Chaos prevailed on the mountain. Trees started falling down. Many evil beings died. The birds started flying off into the skies.
Hanumana took the name of Rama and jumped. The force that was created uprooted trees and animals from the mountain.

Hanuman was in the sky, going towards Lanka.
The Gods approached Surasa, the mother of the snakes. They told her Hanumana, son of Pavan was flying towards Lanka to achieve a task of Rama. She task was to find out how strong he was.

Surasa took the form of a huge rakshashi. She came in front of Hanumana and started obstructing his way.
She said she was hungry and wanted to eat him. She thanked the Gods for sending him as her food.

Hanumana said he wanted to be excused. He was going on a mission and when he returned with the news of Sita, he would then after the giving the news to Rama, enter her mouth.

Surasa said she did not care. He was food for her, and she would not let her go.

Saying this she opened her mouth wide. She made her mouth become twenty yojanas. Hanumana grew upto thirty yojanas and Surasa's mouth became fourty yojanas. Hanumana became larger and Surasa also became increased her mouth size.

Hanumana realized this was not an ordinary rakshashi. He entered her mouth. Surasa closed her mouth and Hanumana becoming as small as a thumb, came out of Surasa's ear. Hanumana said I realize now, having meditated, that you are Surasa, the mother of the Nagas. Please permit me to proceed further.

Surasa assumed her own self and blessed him. She said she had been sent by the Gods to test him and she said she knew he would succeed.