Janmajeya asks a question

Janmajeya asked - You have told me about the great war where in the end only three warriors were left off the Kauravas.
Dhritarashtra hearing his sons were dead, how did he react? A son like Duryodhana was dead. How did his parents behave? How were the last rites of the departed performed?

Do tell, O sage.

The sage said Listen to me while I tell you all that happened.

Astika at the sacrifice

Entering the hall, Astika started reciting shlokas from the Vedas. He then started praising Janmajeya and his ancestors. Pleased the king asked him to ask for something for himself. Astika said he did not want anything. The king said he was looking for Takshaka. Astika said, Takshaka had taken refuge with Indra.
Janmajeya was angry. How dare Indra give shelter to an enemy?

Janmajeya's sacrifice

Tons of clarified butter, clothes and grains were ordered to get the snake sacrifice ready. All great rishis were invited for the event. With the chanting of the vedic mantras, the holy fire was lit.
The sages presiding over the sacrifice started by taking the names of nagas. Pulled by the power of the mantras, they got pulled into the fire. Soon the air was full of the stench from burning snakes.
Takshaka seeing this, along his followers ran and hid in Indra's abode.
Vasuki, the king of Nagas saw this. He asked his sister to send for Astika.
When Astika came, his mother told him, 'Our mother had cursed us to be destroyed in the snake sacrifice of Janmajeya. It had had also been said that you, Astika, will be the one who will save teh nagas from their destruction. Please go and stop this destruction'.

Astika left for the place where the sacrifice was happening. He was not allowed inside the sacrificial hall. Astika got angry and told the guards stopping him, were they not aware that stopping a brahman was not proper. The guards not knowing what to say,allowed him to go inside.

Janmajeya decides

Janmajeya's ministers spoke to him. 'Your father was great king. He was out hunting when he accidentally placed a dead snake on a sage who had taken a vow of silence. Angry his son cursed your father to die by the bite of Takshaka. There was a sage who could have helped your father, but Takshaka intervened and did not let him save your father.'.
Janmajeya wanted to know how the ministers knew about the conversation between the sage and Takshaka. They said 'When Takshaka had destroyed the tree, there was a woodcutter on the tree. He was burnt along with the tree. When the sage revived the tree, the woodcutter was revived along with the tree. It is from this person that we heard this story'.
Janmajeya said what you have said is true and  what Uttanka is also true. Takshaka is the root of many evils.
He called for his priests and asked what to do.
They discussed among themselves and decided to have a sacrifice to destroy the snakes.
Invitations were sent out to all to attend the sacrifice.