Minor spoilers for Dungeons of Cirith Gurat.
Quest card 1 says " Starting with the first player, each player discards cards from the top of his deck until an ally that is not in play is discarded and attaches that ally to an unattached enemy in the staging area."
What does it mean by "an ally that is not in play?" I believe Battle of the Pelennor Fields uses the same wording on ones of its quest stages. Does this mean you can't have 2 copies of Master of the Forge, for example, be captured? Or is this text just there in case the Forced effect would try to put a unique ally into play when another copy of that unique ally is already in play?