"Vaisampayana said, 'When everyone had failed, Drona smilingly called Arjuna and said unto him, 'By thee the aim must be shot; therefore, turn thy eyes to it. Thou must let fly the arrow as soon as I give the order. Therefore, O son, stand here with bow and arrow for an instant.' Thus addressed, Arjuna stood aiming at the bird as desired by his preceptor, with his bow bent. An instant after Drona asked him as in the case of others, 'Seest thou, O Arjuna, the bird there, the tree, and myself?' Arjuna replied, 'I see the bird only, but nor the tree, or thyself.' Then the irrepressible Drona, well-pleased with Arjuna, the instant after, again said unto that mighty car-warrior amongst the Pandavas, 'If thou seest the vulture, then describe it to me.' Arjuna said, 'I see only the head of the vulture, not its body.' At these words of Arjuna, the hair (on Drona's body) stood on end from delight. He then said to Partha, 'Shoot.' And the latter instantly let fly (his arrow) and with his sharp shaft speedily struck off the head of the vulture on the tree and brought it down to the ground. No sooner was the deed done than Drona clasped Phalguna to his bosom and thought Drupada with his friends had already been vanquished in fight.
"Some time after, O bull of Bharata's race, Drona, accompanied by all of his pupils, went to the bank of the Ganga to bathe in that sacred stream. And when Drona had plunged into the stream, a strong alligator, sent as it were, by Death himself seized him by the thigh. And though himself quite capable, Drona in a seeming hurry asked his pupil to rescue him. And he said, 'O, kill this monster and rescue me.' Contemporaneously with this speech, Vibhatsu (Arjuna) struck the monster within the water with five sharp arrows irresistible in their course, while the other pupils stood confounded, each at his place. Beholding Arjuna's readiness, Drona considered him to be the foremost of all his pupils, and became highly pleased. The monster, in the meantime cut into pieces by the arrows of Arjuna, released the thigh of illustrious Drona and gave up the ghost. The son of Bharadwaja then addressed the illustrious and mighty car-warrior Arjuna and said, 'Accept, O thou of mighty arms, this very superior and irresistible weapon called Brahmasira with the methods of hurling and recalling it. Thou must not, however, ever use it against any human foe, for if hurled at any foe endued with inferior energy, it might burn the whole universe. It is said, O child, that this weapon hath not a peer in the three worlds. Keep it, therefore, with great care, and listen to what I say. If ever, O hero, any foe, not human, contendeth against thee thou mayst then employ it against him for compassing his death in battle.' Pledging himself to do what he was bid, Vibhatsu then, with joined hands, received that great weapon.
The preceptor then, addressing him again, said, 'None else in this world will ever become a superior bowman to thee. Vanquished thou shall never be by any foe, and thy achievements will be great.'"