7. Drona Parva

With Bhishma fallen, Dronacharya takes command, and the war changes character. Drona's brief from Duryodhana is to capture Yudhishthira alive, and to do it he forms the chakravyuha — a spiral formation almost nobody in the Pandava army knows how to enter.

Abhimanyu does. He is sixteen, and he learned the way in while still in his mother's womb; he never heard how to get out. He breaks the formation, holds it open, and the Kaurava commanders close it behind him. What follows is the epic's clearest account of a rule being abandoned: six maharathis, Drona and Karna among them, surround one boy, cut his bowstring, break his chariot, and kill him with his own wheel in his hands. Jayadratha's holding of the gate is what kept the other Pandavas out.

Arjuna returns and vows to kill Jayadratha before the next sunset or enter fire himself. The entire fourteenth day is built around that vow; Krishna veils the sun, the Kauravas relax their guard, and Arjuna takes Jayadratha's head as the light returns. The fighting continues into the night — Ghatotkacha's rampage forces Karna to spend the Shakti, the one-use weapon he had saved for Arjuna. And on the fifteenth day comes the half-truth: Bhima kills an elephant named Ashwatthama, and Yudhishthira, who has never lied, says that Ashwatthama is dead, adding 'the elephant' so quietly that Drona does not hear it. Drona lays down his weapons in grief and Dhrishtadyumna beheads him.