Narayani Army enters the battle and Abhimanyu steps in the formation

In the camp Duryodhana went to Drona and asked what was the way to win the war. Drona said You got the Narayani army from Krishna. Let them take Arjuna someplace and fight with him. With Arjuna away, Yudhistira can be captured.
Duryodhana sent for Susharma who was leading the Narayani army and explained the plan to him. He was to take Arjuna northwards.

The battle started. Arjuna was challenged to a fight by Susharma. Arjuna agreed. Susharma thought this was his chance to kill Arjuna. He was happy. Karna and Drona saw Arjuna being led away and they were happy.

Drona said he would form a formation never seen before. Saying this he decided to form the chakravyuha formation. This was a very complex formation and it was very critical for one to knowhow to enter the formation and also how to come out of it. Jayadratha was at the opening of the formation and the other warriors were inside.

Drona saw Yudhistira and began shooting arrows at him. Yudhistira retaliated by shooting arrows back cutting off the horses and killing the charioteer. Drona jumped off and ran to grab Yudhistira. Seeing this, Dhristadyumna came and faced Drona. Yudhistira took shelter with Nakula. So ferocious was the fight that Drona was injured and fainted.

Coming to his senses, Drona then attacked Dhristadyumna, wounding him till he started bleeding.
Draupadi's brother retaliated and attacked Drona again.
He then jumped off his chariot and climbed up on Drona's chariot. There he cut off the horses and killed the charioteer.Drona then shot an arrow which pierced Dhristadyumna. The prince fell on the ground. Seeing him fall, the other Pandava warriors started shooting arrows at Drona.

Yudhistira was wondering how to penetrate the formation that Drona had formed. Arjuna was somewhere else, fighting. He then remembered Abhimanyu. He asked Abhimanyu.

Abhimanyu said I know how to get in but I do not know how to come out. Let me tell you how this happened. When I was in my mother's womb, my mother had heard from my father the way to enter the formation but Arjuna had not mentioned the way out. This is the reason I am not aware of the way out.

Yudhistira said Do not worry. When you enter the formation, we will all be behind you. We will all enter the formation with you.

The brave Abhimanyu said he would fight a battle like never seen before and agreed to enter the formation.

Abhimanyu entered the formation shooting arrows everywhere. Jayadratha who was guarding the formation managed to prevent the other Pandavas from entering the formation. 

Birth of Dhrishtadyumna and Draupadi

Kunti and her sons stayed in the house of the brahmana. A priest one day came there. He spoke about his travels and the places he had visited. He spoke about the land of Panchala and also of the swayamvara of the daughter of the king of Panchala. He priased Drupada's daughter who was called Krishnaa who was very beautiful. She was also called Yagyaseni as she had been born from a sacrifice (Yagya). Drupada, King of Panchala, had also obtained a son from the sacrifice, who would cause the end of Drona.
The Pandavas wanted to know why the son would bring an end of Drona.
The priest said once, Drona and Drupada were great friends. Drona was insulted when he had visited Drupada. He went back to Hastinapura and taught the Kuru princes. He asked the kuru princes to get him Drupada as a prisoner.
Arjuna, son of Kunti, achieved this.
Drupada, when freed roamed the banks of Ganga, lost in thought. He wanted to find out ways in which he would bring an end of Drona. He found two brahmanas, Yaja and Upyaja and was told they may be able to help him.
Drupada went to Upyaja and asked for his assistance in finding a way to get rid of Drona, son of Bharadwaj. Upyaja said it was not proper for a brahmana to hold a sacrifice to kill another. When the king was insistent, Upyaja told Drupada to go to his elder brother, Yaja, and ask for his help.
Drupada went to Yaja with his prayer.
Yaja agreed and Drupada made arrangements to start the sacrifice. He fasted as per rituals along with his queen.
A son came out of the fire, his body the color of fire, with a bow and arrow in his hand. Followed by the boy, a girl came out of the fire. When she emerged, mantras could be heard from all directions.
A voice from the heaven said this girl will be the cause of the death of many kshatriyas. The boy will be killer of Drona.
The king named the son Dhrishtadyumna. The girl, as she was dark in complexion was named Krishnaa.

The priest ending his story said this was the girl, whose swayamvara was being arranged. As the daughter of Drupada, she was also named Draupadi.
The Pandavas wanted to go and attend the swayamvara ceremony.
Kunti said they were living for many days in a person's house and that was not a very good thing. They agreed to go towards Panchala.
At that moment, Vyasa came there. Seeing Vyasa, all bent down and bowed at his feet.