Surasa

Surasa's encounter with Hanuman in the Sundara Kanda Book of the Ramayana and its retellings, is the most popular tale related to Surasa. Hanuman, flies over the ocean to Lanka in search of his master Rama's kidnapped wife Sita. The gods, gandharvas and sages call Surasa, the mother of the nagas, and request her to assume a terrible rakshasi (demoness) form to test Hanuman's strength (bala) and thinking power (buddhi). 

Surasa consents and obstructs Hanuman's path in the sea. She has solar imagery, with “yellow eyes and a pair of jaws fanged and gaping” and the size of a mountain. She declares that Hanuman is the food provided to her by the gods and tries to eat him. Hanuman explains his mission to track Sita and requests her to let him go, and promises to return to enter her mouth, in accordance to Sama (gentle persuasion) and Dana (earnestly asking) part of the Sāma, Dāna, Bheda, Danda philosophy. She tells him that he can pass only through her mouth, as per a boon given to her. Hanuman counters her by challenging to open her mouth wide enough to eat him (Bheda – threat). He starts expanding his form and becoming larger; Surasa also expands her jaws so she can devour Hanuman; the contest is interpreted as danda (punishment). Finally when Surasa's mouth expands to a 100 yojanas, Hanuman suddenly assumes a tiny form (size of a thumb) and enters her mouth and leaves it, before she can close it. Thus, Hanuman respects Surasa's vow as well as saves his life. He salutes her and addresses her as Dakshayani (daughter of Daksha). Impressed by Hanuman's "ingenuity and courage", Surasa assumes her true form and blesses Hanuman. Surasa allegorically stands for sattvika maya, the purest form of illusion that needs to be tamed but still respected.