When Drona was teaching martial arts to the Kaurava princes, princes from many countries flocked to him. One of them was Ekalavya, son of Hiranyadhanus, King of the Nishadas. Since the Nishadas were of a mixed race, they were considered to be of a lower order in the social hierarchy. Therefore, Drona expressed his inability to accept Ekalavya as his pupil, in keeping with the conventions observed at that time.
Ekalavya took leave of Drona after paying obeisance to him by touching Drona's feet. He went back to his place in the woods. He made a clay image of Drona and began to practice archery in front of the statue.
As a result of his abiding faith, deep devotion, sustained focus and persistent efforts, Ekalavya was soon able to acquire a high level of skill in archery. His skills in all the three areas viz, fixing the arrow on the bowstring, aiming the arrow and releasing it at the right moment were outstanding.
Once, the Pandava and the Kaurava princes went on a hunting expedition. They took along a dog for helping them in hunting. The dog strayed away and came to the place where Ekalavya was stationed.
Looking at Ekalavya, the dog began to bark, considering him to be an undesirable person. Ekalavya
sent seven arrows into the mouth of the dog with a view to silencing the dog. The dog returned to the camp of the princes, with the arrows embedded in its mouth.
The princes were amazed by the skill of the person who had sent the arrows into the mouth of the dog. They went in search of him. When they found Ekalavya, they asked him who he was. Ekalavya introduced himself as the son of the Nishada King Hiranyadhamus and as a pupil of Drona.
The Pandavas returned to the palace and told Drona about the extraordinary skill in archery displayed by Ekalavya. When Arjuna was alone with Drona, he asked him "You told me that no disciple of you would be equal to me. How is it that Ekalavya has superior to me in skill?"
Drona reflected on the question posed by Arjuna. He momentarily decided upon the course of action. He went to Ekalavya, taking Arjuna along with him..
After spotting Drona from a distance, Ekalavya ran towards him and fell at his feet. Drona told him, "Oh, King of Nishada, if you are a disciple of me as claimed by you, should you not offer me the Gurudakshina (remuneration payable by a student to the teacher)?"
Ekalavya replied, "You are my teacher. Please tell me what Gurudakshina I should give you. I will offer whatever is desired by you."\\
Drona said, "Please give me the thumb of your right hand. That is the Gurudakshina I seek from you."
Ekalavya cut off his right thumb without even a moment of hesitation and offered it to Drona.
with a cheerful face.
After this, Ekalavya tried to fix an arrow on his bow using the remaining four thumbs and aim at a target. He found that he had lost his dexterity. Arjuna was relieved that the only person in the world who was superior to him in skill had the skill taken away from him.