Stricken Dumb
The Black Riders#64 (x3/x3)

When Revealed: You must either shuffle the top card of the burden deck into the encounter deck and reveal an additional encounter card, or raise each player's threat by 3 and immediately end the quest phase (do not resolve the quest).

Then the leader, who was now half across the Ford, stood up menacing in his stirrups, and raised up his hand.
-The Fellowship of the Ring