He raped, pillaged, and burned. The atrocities he committed, which then extended into other Dark Realm kingdoms, spurred people like Storshae, Toono, and Apoleia into the directions they took. They followed a similar path of destruction to those around them in their search for vengeance or redemption, but they had been dealt with or confronted already.
Mendac was the cause of everything in the first 5 books.
