Karna spares Sahadev's life

Overview

Karna spares Sahadev's life on remembering his promise to Kunti. Bheem kills an elephant named Ashwathama. Dronacharya decides to destroy the universe when Yudhishthir tells him about Bheem attacking Ashwathama. Who will make Dronacharya realise the mistakes he made while bringing up Ashwathama?