Flee the City
The Sands of Harad#67 (x1)
2A-B (15)
When Revealed: End the current phase. Shuffle the encounter discard pile into the encounter deck. Starting with the first player, each player discards cards from the top of the encounter deck until he discards an enemy, and puts that enemy into play engaged with him.

The whole of Umbar is astir, and the Southrons chase you through the streets. If you cannot escape the city quickly, you are certain to be taken prisoner.
This stage cannot have more than 15 progress tokens on it.

Forced: At the beginning of the quest phase, if any player is not engaged with an enemy, discard cards from the top of the encounter deck until an enemy is discarded and add it to the staging area.

While at least 1 player is engaged with an enemy, the players cannot defeat this stage. If the players defeat this stage, they win the game.