You are playing Nightmare mode.
Forced: When stage 1B is revealed, the number of random heroes captured is determined by the number of players, as follows: 1-2 players = 1 hero captured, 3 players = 2 heroes captured, 4 players = 3 heroes captured. All captured heroes are turned face down and considered "the prisoner," cannot be used, cannot be damaged, and do not collect resources until they are rescued, (A single player cannot have more than 1 hero captured by this effect.)
Begin with the standard quest deck and encounter deck for the Escape from Dol Guldur scenario found in the LOTR LCG core set.
Remove the following cards, in the specified quantities, from the standard encounter deck:
2x Dol Guldur Orcs
2x Enchanted Stream
1x Great Forest Web
3x Mountains of Mirkwood
2x Caught in a Web
1x The Necromancer's Reach
1x Necromancer's Pass
2x Under the Shadow
2x Tower Gate
1x Iron Shackles
Then, shuffle the encounter cards in this Nightmare Deck into the remainder of the standard Escape from Dol Guldur 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.