I went though the castle and killed everyone and didn't get it. So I checked my queslt helper and it was showing outside of the castle so I went out and found it.
EASIEST WAY TO GET THIS:
Come in the gates and head to the castle entrance. When you get there turn left BEFORE going up the stairs into the castle. Go to the corner and turn right. There is a demolished build there that had a thief and conjurer when I was there. I watched two guys doing the same quest kill those guys and get the Sigil, so I killed them and got it off of the Conjurer. Saw a couple other people running around told them where to go and all 3 of them got it off those two guys.
It may drop randomly, but for it to drop on the same mob 6 times of 6 spawns, seems a little less than random.
No promises, but certainly worth a shot.
EASIEST WAY TO GET THIS:
Come in the gates and head to the castle entrance. When you get there turn left BEFORE going up the stairs into the castle. Go to the corner and turn right. There is a demolished build there that had a thief and conjurer when I was there. I watched two guys doing the same quest kill those guys and get the Sigil, so I killed them and got it off of the Conjurer. Saw a couple other people running around told them where to go and all 3 of them got it off those two guys.
It may drop randomly, but for it to drop on the same mob 6 times of 6 spawns, seems a little less than random.
No promises, but certainly worth a shot.