Bilbonic the Plague was one of the brave adventurers who was dedicated to help better society by ridding the world of magic, under the command of Mir Yannick. Although he was not selected for the expedition into an unknown region of the Great Underground Empire that had been discovered in 1066 GUE, Wartle felt that because of the amount of grues within that vicinity that he should have been sent instead.

SOURCE(S): Zork: The Undiscovered Underground