Sahadeva kills Shakuni

With his Gandiva in his hand, Arjuna began killing the Kaurava soldiers.
Duryodhana was fighting Dhristadyumna. Dhristadyumna cut off Duryodhana's chariot and the king had to run away. He fell in the ground and ashamed he ran off where Shakuni was.
In the meanwhile, Kritavarma was fighting Bhima. Bhima managed to control Kritavarma.
Duryodhana returned back to fight. Arjuna continued killing the soldiers. He killed Susharma. Susharma's son came to fight and also met his end.
Sahadeva and Shakuni were fighting, aiming weapons at each other. Sahadeva cut off Shakuni's bow. Shakuni took another bow. Shakuni's son, Ulluka, came to assist his father. He met his end in the hands of Bhima, who killed him with a crescent arrow.
Angry at his son's death, Shakuni started aiming arrows at Sahadeva. Sahadeva cut off all the arrows and his bow. Shakuni then took a spear and used that on Sahadeva. Sahadeva cut that off. Whatever weapons Shakuni aimed at Sahadeva were cut off. Sahadeva then cut off Shakuni's chariot. He started walking away and Sahadeva began clapping saying the Kshatriya runs away.
Hearing this, Shakuni came back and resumed fighting. Whatever weapons he used, Shakuni cut those off. Tired, Shakuni fell on the ground. Sahadeva grabbed Shakuni by his hair and dragged him. Sahadeva said You are the root of all problems. You cheated us in dice. I will make you pay for that.
Shakuni said Kill me but do not insult me.
Sahadeva cut off Shakuni's head.
Duryodhana , Kritavarma, Kripacharya and Ashwatthama were the only strong warriors left in the Kaurava camp.

Sahadeva plans to kill Shakuni

Duryodhana agreed to lead the army. He soon came across Bhima. They started abusing each other and then began fighting. Defeated by Bhima, Duryodhana fled.
Bhima attacked the army with his mace.
The king Shalva came to fight. He came on a elephant. The elephant was killed by Dhristadyumna. The king jumped off the elephant and was attacked by Satyaki. Satyaki cut off Shalva's weapons. Seeing this, Kritavarma came to his rescue. Satyaki aimed arrows at Kritavarma, who had to flee. Shalva and Satyaki began fighting again and Shalva met his end in the hands of Satyaki.
Seeing this, Kritavarma came again and attacked Satyaki. Satyaki cut off the chariot of Kritavarma. Kripacharya pulled Kritavarma on his chariot.
Duryodhana came to fight with his bow and arrows.
Yudhistira and Shakuni began fighting. Shakuni cut off Yudhistira's chariot. Seeing this Yudhistira jumped on the ground. Sahadeva seeing this, picked up Yudhistira on his chariot.
The Pandavas began planning to kill Shakuni.
Shakuni came to fight with Duryodhana supporting him.
Sahadeva was excited. He remembered that he had promised to kill Shakuni. With the armies fighting each other, Sahadeva and Shakuni also began fighting, and the sky was covered with arrows.
Shakuni was fighting fiercely and the Pandava army started stepping back. Seeing this, Krishna said -Why is this happening? The army that could stand Bhishma, Drona and Karna should be able to withstand the might of Shakuni. Kill Shakuni today.

Arjuna went ahead and started slaughtering the Kaurava army. 

Karna comes to fight again

Seeing Ashwatthama without weapons, Karna rushed to his rescue.
Arjuna said You ridiculed the Pandavas and enjoyed the humiliation of Draupadi. I will teach you a lesson you will not easily forget.

Karna said Let me see your skills. Use all your weapons on me. See if you can do anything.

Arjuna said If you had some shame you would not have said this. I killed your brother and you fled.

Arjuna and Karna then began fighting showering arrows on each other.

Arjuna then killed the charioteer of Karna.

All weapons finished, KArna has no option but to leave the battlefield.

Arjuna then spotted Shakuni and went close to him . Shakuni tried to flee and Arjuna chased him. Catching up with him, Arjuna said You are the cause of all troubles. Let us play a game of dice with arrows. I will not fill you as Sahadeva has promised to do that.

Arjuna shot arrows and the chariot of Shakuni started spinning. Shakuni, not able to control this, ran away.