Searching for a Way Out
The Wilds of Rhovanion#28 (x1)
Lost in Mirkwood
Each objective-location, and each card guarding one, is immune to player card effects.

Forced: When progress would be placed on the main quest, if there are no objective-locations in play, discard an equal number of cards from the encounter deck instead. Then, put the topmost objective-location in the encounter discard pile into play.