Drona is a renowned instructor of all the skills of battle, but especially archery, in the Mahabharata, the second of the two major Hindu epics.
He is the martial instructor of both the Pandavas and the Kauravas, the two royal factions at the center of the Mahabharata's power struggle.
Drona is the son of the sage Bharadvaja, who was born when the sage saw a heavenly nymph and had an involuntary seminal discharge (apsara).
Drona's weapon talents come from the deity Vishnu's incarnation, Parashuram, who bestows both his weapons and abilities to Drona as a blessing.
Drona's archery proficiency is legendary, as is his ability to teach archery.
He has a special liking for Arjuna (a Pandava sibling), who demonstrates such dedication and focus that Drona tells Arjuna that he will become the world's best archer.
The tale of Ekalavya, a tribal kid whom Drona refuses to educate because of his low position, but who becomes Arjuna's equal as an archer by worshiping a clay figure of Drona, exemplifies this support for Arjuna.
When Drona learns of this, he insists that Ekalavya hand up his right thumb as a preceptor's fee, ensuring that no one would be able to compete with Arjuna.
Drona battles heroically on the side of Duryodhana (Dhrtarashtra's oldest son) during the Mahabharata war, but is eventually murdered by King Drupada's son Dhrshtadyumna.
Drupada and Drona have a lengthy history of feuding throughout the epic.
They lived together as students, but after their studies are through, Drupada ascends to the throne of Panchala, whilst Drona is so destitute that he cannot support his family.
When Drona begs Drupada for charity, Drupada upbraids him in the most offensive way possible.
Drona swears vengeance, and after teaching the Pandavas and Kauravas the skills of battle, he demands Drupada's kingdom as a teacher's fee (dakshina) from his pupils.
Drona steals part of Drupada's kingdom after he defeats him, and Drupada swears to avenge him.
Drupada then undertakes a massive fire sacrifice in order to have a son who would slay Drona.
Two radiant children emerge from the flames, one of them is Dhrshtadyumna and the other his sister, Draupadi.
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