You are playing Nightmare mode.

For at that time the realm of Angmar arose in the North beyond the Ettenmoors. Its lands lay on both sides of the Mountains, and there were gathered many evil men, and Orcs, and other fell creatures.
–The Return of the King

Begin with the standard quest deck and encounter deck for The Dread Realm scenario.

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

3x Witch of Angmar

2x A Fell Dread

1x Unholy Crypt

1x Sinister Dungeon

2x Dead Lord

3x Terror of the North

Then, shuffle the encounter cards in this Nightmare Deck into the remainder of the standard The Dread Realm encounter deck.

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