Pytho's Mask (2001)

On the Night of the Comet, the usual astrological bonds do not hold, and the order of the universe is threatened. It is a time made for rebels and usurpers, and all who would claim the kingdom for themselves. You are a member of the Order of the Phoenix, a protector of the hierarchy and the kingdom itself. It is your duty to attend the royal ball, watch for dangers... and do whatever needs to be done. A piece of Interactive Fiction written by Emily Short.