What happens if I save Berthold and his sister?
There's a spot behind the High Overseer's office where a woman is being accused of being a witch. Her brother, Berthold, is trying to defend her. When negotiations go sour, Berthold draws his sword and kills one of the guys, The other one then stabs him in the back and goes after his sister.
I didn't get my crossbow out fast enough to save Berthold, but I was able to sleep dart the surviving overseer in time to save his sister. She ran out to Holger Square and disappeared.
What would have happened if I had been able to save them both?
If you save them both, the brother, Berthold, will reward you by giving you the code to the safe in the squad barracks.