Potentially a very strong card, since there are any number of seriously tough non-unique enemies. With some 40 unique warriors, and 12 unique scouts it shouldn't be too hard to find a combo that works. The main disadvantage is how conditional it is. Like many of the staging-area effecting events, unless you face the specific problem it aims to solve at the time you have it to hand, it is useless. It only works on an enemy that stays in the staging area at least one round, although there are combos in Leadership which help with that (Anborn, Fresh Tracks). I wouldn't play this, therefore, in a general deck. But it might come in against a specific scenario with particularly nasty staging-area enemies.
Play only if you control a unique character with the Warrior trait and another unique character with the Scout trait.
Response: After the players have committed characters to the quest, discard a non-unique enemy in the staging area. Then, reveal an encounter card.
Beneath the Sands #57. Leadership.