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.