You are playing in Nightmare mode.

While Doors of Durin is in play, The Watcher cannot be engaged.

Forced: When a Tentacle enemy is destroyed, deal 1 damage to The Watcher if it is in play.

The players cannot win the game unless both Doors of Durin and The Watcher are in the victory display.

"Something has crept, or has been driven out of dark waters under the mountains. There are older and fouler things than Orcs in the deep places of the world."
–Gandalf, Lord of the Rings

Begin with the standard quest deck and encounter deck for The Watcher in the Water scenario.

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

1x The Watcher

2x Makeshift Passage

4x Black Uruks

3x Mountain Warg

2x Warg Lair

Then, shuffle the encounter cards in this Nightmare Deck into the remainder of the standard The Watcher in the Water 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.