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The Fall of Nargothrond #332 (x4)
Treachery

When Revealed: The first player discards cards from the top of the encounter deck until an enemy is discarded, and adds that enemy to the staging area. Then, the players must remove X characters from the quest, where X is the number of enemies in the staging area.

Shadow: The attacking enemy gets +1 Attack If this attack destroys a character, remove 5 progress from the quest.