You are playing Nightmare mode.

Setup: Add Palace Remains to the staging area.

If there are more Osgiliath locations in the staging area than players in the game, this card gains:"Response: At the beginning of the quest phase, choose 1 non-unique location. If the players quest successfully this phase, remaining progress made beyond the active location's quest points is placed on the chosen location

"This great array of spears and swords is going to Osgiliath." –Frodo, The Two Towers

Begin with the standard quest deck and encounter deck for the Assault on Osgiliath scenario.

Remove the following cards, in the specified quantities, from the standard encounter deck:

4x Uruk Soldier

3x Southron Phalanx

2x West Quarter

2x East Quarter

1x Ruined Tower

1x Ruined Square

2x The Master's Malice

2x Street Fighting

3x Southron Mercenaries

1x Uruk Lieutenant

1x Orc Arbalasters

1x The Power of Mordor

Then, shuffle the encounter cards in this Nightmare Deck into the remainder of the standard the Assault on Osgiliath encounter deck.

Finally, flip this setup card over and place it next to the quest deck. Its effects remain active throughout the game, which is now ready to begin.