1. Go to Sentinel Island
2. Teleport to the "Sea Side Shrine"
3. Look around for a door set into a cliff. It should be nearby.
4. When you try to open it, you should get a prompt for the password. It is Demise.



The imp thing is an unrelated quest. You are missing one piece of parchment found in Broken Valley. They are located:

1. In a chest near the Tribal Teleport Shrine
2. In a chest just across the river from the tribal shrine, in a ruin up top, you'll need to cross the river through a canyon and climb up.
3. In a chest in a ruin between the south-east goblin camp and the south-east mini-bandit camp. From the South Valley shrine, go north.
4. In a chest hidden behind some wood outside the entrance to the large Bandit Camp.