Excellus serves Walhart as his tactician for battles, but was secretly manipulating him. Excellus' skills lie not in war tactics, but his ability to con and deceive others into joining Walhart's army through blackmailing and threats. Excellus cares only for himself, Grima and seizing power, even if it means abandoning his superiors. However, despite his cowardly nature. Excellus was secretly a devout member of Grimleal, and was manipulating Walhart to fail in his quest to destroy the Grimleal. Excellus also took a deal from Aversa which offered him the throne of Plegia if he was able to take the Fire Emblem from Chrom.