They cast lots to determine the perfect day (Esth 3:7-3:9)

“In the first month, which is the month of Nisan, in the twelfth year of King Artaxerxes, Heman came to a decision by casting lots. This casting of lots takes the days and the months one by one, in order to fix on one day in order to destroy the whole race of Mordecai. The lot fell on the fourteenth day of the month of Adar, which is the twelfth month.”

Haman came to a decision on when to destroy the Jews by casting lots, known as pur. This was a common practice in the Middle East. It happened a lot in the biblical literature, even for such important things as allocating the land for the tribes of Israel in Joshua, chapters 14-19. This was now the 12th year of King Artaxerxes, 5 years after Esther has become queen. There never seems to be any mention of the king’s children, either with Queen Vashti or Queen Esther. The date chosen for destroying the race of Mordecai is the 14th day of the 12th month, so that there will 11 months to get ready for this perfect massacre day.