Watchful Eyes
The Dark of Mirkwood #40 (x1/x0)
Treachery

When Revealed: The first player attaches Watchful Eyes to one of his heroes. (Counts as a Condition attachment with the text: "Limit 1 per hero.Forced: If attached hero is exhausted at the end of the combat phase, reveal 1 card from the encounter deck and add it to the staging area.")