Waking Nightmare Waking Nightmare is a quest available in . Background . The people of Dawnstar are not sleeping well , because they are all experiencing terrible nightmares . Erandur , a priest of Mara , wants the Dragonborn ' s help to destroy the Skull of Corruption , which will release Vaermina ' s hold on people ' s dreams . Walkthrough . This quest is given after visiting Dawnstar and speaking to Erandur , who is in the Windpeak Inn . All the townsfolk are suffering the same nightmares and Erandur knows how to get rid of them . He wants the Dragonborn to travel with him to the Nightcaller Temple , which is just a short distance east of Dawnstar , to stop the nightmares . If pressed for details , he simply insists that the Dragonborn needs to trust him as a priest of Mara . The entrance to Nightcaller Temple is the home of three frost trolls . Snow Bears , Snowy Sabre Cats , Ice Wraiths or Frostbite Spiders may be there instead , depending on the Dragonborn ' s level . At the entrance , Erandur warns about the dangers within . Priests and orcs battled , until a gas called the Miasma was released that put everyone ( both priests and orcs ) to sleep . He fears that , when the doors are opened , the gas will dissipate , and everyone will wake up and be hostile . Once inside , the quest mainly requires the Dragonborn to follow Erandur . Erandur will cast a fire spell on the wall to create an opening . In the next room , Erandur points out the Skull of Corruption , and says that the inner sanctum must be entered . Following him down a curving set of steps leads to some leveled orcs waking up that will attack if given the chance , and a blue barrier . When the barrier is reached , Erandur reveals himself as a former priest of Vaermina who ran away during a long - ago attack on the temple by the orcs . He became a priest of Mara and now wishes to resolve loose ends in the Temple . In order to pass through the barrier it will be necessary to go to the library to find the book " The Dreamstride " . There will be Vaermina Devotees to fight along the way and inside the library . Upon locating the book , Erandur states that there is a way to pass the barrier , but it requires Vaermina ' s Torpor , a potion that allows the user to travel by following another ' s dreams . The next stop will be the laboratory , where Vaermina ' s Torpor is stored . There are some more invader Orcs and Vaermina Devotees that will need to be dealt with along the way . The Torpor is located on the shelf in the corner of the laboratory . It is next to three lit candles on the wall . When Vaermina ' s Torpor is located , Erandur instructs the Dragonborn to drink it and upon doing so , he or she becomes Casimir , a Vaermina Devotee during the Orc raid on the temple . Casimir is instructed to release the Miasma to protect the Skull . After releasing the Miasma by pulling a large ring on a chain on the wall just to the left of the barrier , the Dragonborn will find themselves on the other side of the barrier , where they must collect the Soul Gem powering the barrier . Erandur remarks about what happened , and then proceeds to the inner sanctum . As the inner sanctum is approached , Veren and Thorek appear . They are the two Vaermina Devotees that told Casimir - the Dragonborn in the dream - to release the Miasma . After some short dialogue that reveals Erandur to be Casimir , they become hostile . After the battle , Erandur casts a spell to destroy the Skull of Corruption . Here the choice is to kill Erandur as Vaermina commands and take the Skull of Corruption or let him complete his spell to destroy the Skull . If he lives , he can be a follower for no charge . However , this gives up the chance to acquire one of the Daedric artifacts , which are needed to obtain the Oblivion Walker achievement . See the Nightcaller Temple article for more details on available items .