XANDER CAGE
Member
You don't need to fight the drake in Devilfire. You can hug the mountains to keep it from ever spotting you or you can just run like hell when it sees you.
If I'm remembering the cypher quest correctly you're looking for the Black Cat. It's down near the southeastern corner of Gran Soren in a small alley. If you've done the mission for Mason where you have to tail someone at night then the place you tailed the guy to is Madeleine's shop, which is directly across the street from the Black Cat.
Usually your pawns will mention something about having forgeries made or talking to the scrivener when you get near to the Black Cat, which is an easy way to know you're nearby. It's a little tucked away and kind of easy to miss. If all else fails you could go find Fournival in the Noble's Quarter. If you just stick with him long enough eventually part of his daily routine has him visit the Black Cat.
Oooh, ok, that makes more sense. The quest dialogue says "reclaim the fortress from the dragon" or something, so I assumed I had to fight that drake.
I'd already spoken to the Black Cat, but after another 10 minutes of running around I finally got a quest marker taking me to the next person in the quest chain.