“Your Majesty, you know that I will gladly lay down my life for an honorable cause! But these orders- and all of our recent actions- they are not just! If I saw any way in which this invasion protected Grado, I would hold my tongue. But now, Renais is left ungoverned to drown in chaos, and we gain nothing! Why do you wage this war? What is it you hope to achieve? You've sent our men to fight and die for nothing! This isn't war- it's murder!”

Known as the "Obsidian", Duessel is one of Grado's Six Generals. Along with Selena and Glen, Duessel is one of the Imperial Three, the three original Generals before the invasion of Renais. He is characterized by his martial prowess, honor, and his will to fight for the greater good. He trained Ephraim at one point, and both of them are good friends. Throughout the Story, Duessel had been questioning the Emperor's actions, such as making Riev, Caellach, and Valter generals, and the war itself. This indicates that he has high moral values.