What story does Schaffa tell Damaya on their journey?

Schaffa tells Damaya the story of Shemshena and Misalem. Misalem was an orogene who decided to kill the emperor. He killed thousands of people in several towns, cities, and commless warrens. When he approached Yumenes he sent word that he wanted the emperor to meet him and die. When Shemshena, the emperor's bodyguard, heard the news, she had every citizen of Yumense leave town along with all the livestock and the crops. They even cut down the trees and shrubs and burned them and houses. They doused the fires to leave only ash. When Misalem came, he tried to draw on the power of the Earth, but there was nothing to draw power from. Shemshena killed him.