Drona steals part of Drupada's kingdom when Drupada is vanquished, and Drupada vows vengeance.
He makes a significant sacrifice in order to give birth to a son who would assassinate Drona.
Dhrshtadyumna, who finally kills Drona, and Draupadi, who becomes the wife of all five Pandavas, are the two offspring that emerge from the sacrifice fire.
During the Mahabharata battle, Drupada fights with his sons-in-law, the Pandavas.
Drona finally kills him in combat, but his son Dhrshtadyumna avenges him by killing Drona.
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