"Shoot the remaining guards on the roof" is an objective in the mission Johnson's Errand
After getting the Stolen Chest from the Bandit Fort, some bandits will ambush you from the roof of one of the houses. Kill them using your firearm.
Dialog[edit]
Thomas: Come on, now. It's just a few fools with knives... they ain't so tough.
Thomas: Oi! Mister Johnson's gonna need ta double my pay after all dis if he expects me to keep at'is side.
