Eriador Wastes
Travel: The first player engages a Warg enemy in the staging area and deals it a shadow card.
Slopes of Amon Hen
Travel: A player at this staging area must engage an enemy in any staging area to travel here.
Am I correct in guessing that the difference between these two cards is that for Eriador Wastes you get a free pass if there happens to not be any Wargs in the staging area?