Hey all! I haven't spent much time in Cairo but due to my Nemesis hunt, I'm on my third round in the Catacombs. The first two missions asked that I get secret plans, but this time its asking for an artifact. I think I got one once, when I was looking for the plans the first time, but I haven't seen any since and I keep getting plans (I've gotten five so far).
My question is, is it an either/or situation? You get plans OR the artifact, or am I just missing the artifact on my recent trips?
Any help would be lovely, since I've been stuck in Cairo and running back and forth to deposit plans for a week or so.