In the epic Ramayana, after the death of Indrajit, Ravana's son, Ravana himself entered the battlefield with fury and injured Lakshmana severely with a powerful Shakti spear. The Vanara physician Sushena, upon examining Lakshmana, determined that he still had a chance of survival but required immediate and specific medical attention before daybreak.
Sushena directed Hanuman to retrieve the Vishalyakarani herb from the Gandhamadana Mountain, describing its precise location: on the sixth peak of the mountain, beside a river where medicinal trees with blue flowers, yellow leaves, red branches, and golden vines grew. This herb was essential to save Lakshmana's life.
Hanuman, known for his immense strength and devotion, prepared for the journey. He folded his ears, balanced himself with his tail, and leaped into the sky, growing in size to twenty yojanas (a vast measure of distance) to expedite his travel.
Ravana, determined to thwart Hanuman's mission, dispatched the demon Kalanemi to impede Hanuman. However, Hanuman, with his unmatched prowess, quickly killed Kalnemi and continued his quest. Upon reaching Gandhamadana Mountain, Hanuman struggled to identify the specific herb. In his urgency and immense strength, he decided to lift the entire mountain peak and carry it back to Lanka to ensure he brought the correct herb.
During his return, Hanuman also encountered Bharata, his devotion to Lord Rama evident in their meeting. Hanuman's mission was successful as he arrived in Lanka with the mountain before sunrise. The Vishalya Karani herb was used to treat Lakshmana, reviving and healing him, thus enabling him to return to the battlefield and continue the fight against Ravana.
This episode highlights Hanuman's loyalty, strength, and resourcefulness, illustrating his critical role in the Ramayana and his unwavering commitment to Lord Rama and his cause.