Dreams of the Dead in Skyrim is one of the Creation Club quests available in the Anniversary Edition, but to get started, you'll first need to find Gallow's Hall. The Anniversary Edition adds new fan-created quests, locations, and NPCs to the map, which means there's more content in Skyrim than you can Fus Ro Dah at. The mages among you, in particular, will want to check out this quest as it features necromancy. So, let's take a look at how to get started.
Skyrim Gallow's Hall location
So where exactly is Gallow's Hall? To find it, head to Windhelm then travel southwest to find the entrance built into the rocks near a body of water called Mara's Eye Pond. Head inside and you'll see a dead mage lying in front of an altar surrounded by notes, including Naara's plea and journal. Reading the journal will begin Dreams of the Dead.
How to complete Dreams of the Dead in Skyrim
First, read the Arch Necromancer's first clue. It's on the table behind the body, so just follow the waypoint. You'll read a note that instructs you to pick up the torches that trace the mage's path, beginning with the torch of Morthal to your left. Next, turn left again and cross the room to pick up the torch of Falkreath before getting the torch of the Nightgate Inn and Fort Dunstad.
Next, pick up the fallen Staff of Worms with the skull on it, which is near the pillar. You'll then need to "find a use for the staff", so equip it and then search Naara's body. She'll have a letter called Hooded Skeleton, and you can find said skeleton behind you to the right inside a coffin. Use the staff on the skeleton then interact with it to get the Arch Necromancer's key, which unlocks a safe in the room.
Inside this safe, you'll find the likes of a Bloodworm Helmet, gold, and a Welkynd Stone. You'll also find the Necromancer's second clue, so pick it up and read it. You need to pray to a prince and find a way to the dream world—can you think of a way how? If you guessed 'go for a nap', well done! On the other side of the room there is a shrine to Vaermina, so pray at that before heading to the bedroll beside the dead body and going to sleep. You only need to sleep for an hour, and once you wake, you'll need to find three gems inside a necromancer's coffers.
There are coffins dotted around the room, so search three of them and pick up the Dreamer's soul gems to complete this part. You'll then return to the real world and can find the final instructions note on the red altar. The final Dreamer's soul gem can be found beside Naara on the floor, so pick it up. Place the Dreamer's soul gems on the altar and activate the Altar of the Revenant. Gallow's Hall is now yours and you can summon undead creatures using the altar in the basement, as well as find all sorts of alchemy ingredients around the cave.