King Achashverosh promotes Haman to supreme power, but Mordechai refuses to bow to him as a deity. Infuriated, Haman casts lots to find an "auspicious" date for genocide. He convinces the king to issue a royal decree to destroy all Jews on the 13th of Adar, throwing the city of Shushan into a state of panic. https://www.torahrecordings.com/writings-with-rashi/010_esther/003