High Fructose Corn Syr---Oh wait, wrong thread. "Fighters of the City" seems reasonable. I was thinking "Fist of the City" myself. Perhaps it means "Factions of the City," and is some sort of centralized council or government that moderates the various factions and distributes arms to the Guardians. Assuming this is correct, I would infer that its base of operations is located somewhere within the main tower.