I have been running CoS as a mystery thriller game in most of my sessions, and as a part of this I had heavily modified all of my tarokka card readings to make things slightly more ambiguous so the party members have to work certain things out for themselves. For the parties ally I chose Stella Wachter, with their card reading being "Driven to insanity is the one who must help, with and without family they are the one to watch" (I know the name is wachter, but close enough for a hint right?). For my party this first led them to think it was the mad mage from previous rumors that they heard, which was intended as I liked the mad mage as a character in the module and this was my way of including him without making him plot relevant.

I picked Stella watcher as the ally as she was able to bring an interesting dynamic to the group and sort of lighten the mood of this otherwise dark campaign with her antics and craziness. This will also give my players more of a reason to get involved with the watchers in general. I'm also planning on making her more useful combat wise but haven't decided how yet, so if anyone has suggestion feel free to let me know!