I've just started playing the Khazad-Dûm expansion, and am sure i'm playing it correct, by placing the East-gate as the active location. But since it's a victory-card, it never gets placed in the discard-pile, or the staging area, once explored. And since it's immune to card effects, it can never be removed otherwise.
Then why does it have the big threat strength of 7???
What am i missing?
If the answer is, that it gets used later in some other scenario, then that's great news. But if not, then either it's a fault, that it even has a threat strength, or i'm doing something wrong.