Katrina has dedicated her life to finding the Aetherium Forge. Unfortunately, she died in an earthquake while in the Dwemer underground before she could complete here quest. Now the task falls to you, Dovahkiin. Can you find all the Aetherium shards and survive the perilous Dwemer ruins filled with traps and ancient metal guardians? Well, if you need any help we've made a guide to get you through this massive side quest.
Upon completion, this side quest grants you 30 gamerscore and a very spiffy item. Skip to the end of this little walkthrough to see what’s up for grabs.
To begin this lengthy quest, you can read about it in a book called “The Aetherium Wars” (found in various locations) or simply travel to Arkngthamz. This location is marked on your map automatically once the Dawnguard DLC is installed. It is southeast of Markarth.
Enter Arkngthamz and make your way through it until the ghost of Katria appears and speaks to you. You can have her accompany you to the summit. Make sure to grab her journal from her corpse nearby.
When you reach the Tonal Lock puzzle, strike the locks in the following order: lower left, lower right, upper left, upper right, center. Once inside, grab the Aetherium Shard.
Your next destination is Raldbthar, a mountaintop ruin west of Windhelm. Make your way through this trap-laden place.
When you get to a raised bridge, look for a button to the north (pictured above).
When you get to the set of four buttons, press the second from the right to lower the bars to the left.
When you reach the room with the seized gears, inspect each of the gears in the room for obstructions. There are four obstructions that need to be removed (one of which is in the gear underwater). Once you remove them, press the button to lower a bridge. Defeat the Centurion and proceed through the door behind the spot from which he attacked from.
Continue on and grab the second shard. Use the lift in the room nearby to exit the ruins quickly.
Travel to Mzulft, a ruin southeast of Windhelm. The third shard is not in the ruin itself, but in the Dwarven Storeroom nearby. Inside the storeroom, unlock the gate and claim the shard.
Your next destination is Deep Folk Crossing, which is northeast of Markarth and southwest of Mor Khazgur.
Finding the forge
Travel to the Ruins of Bthalft, which are directly south of Ivarstead and far northwest of Riften. Once there, speak to Katria, who will be waiting for you. Put the shards into the Dwemer Mechanism, then once the crest is assembled, take it out and stand clear. The platform will rise, creating a new entranceway. Use it to descend into the forge.
You’ll eventually reach the locked door pictured above. Shoot both resonators to open the path. When you reach the actual forge, shut off the steam by closing the nearby valves. Once you do, a bunch of dwarven machines will attack.
After you defeat all of the normal machines, the Forgemaster boss will appear. After having been swarmed by so many enemies at once, defeating this one monstrous foe should be an easy task for you. Just be aware that the Forgemaster resists fire attacks.
Using the forge
You are able to craft only one of three items in the Aetherium Forge. Besides the Crest, which you already have, all required materials can be found in a chest to the right. A quest marker shows you where. Possible creations are as follows:
Above: Allows for two simultaneous standing stone effects
Above: Enemies struck by shield become ethereal for 15 seconds (invincible but unable to attack)
Above: Summon a Dwarven Spider or Sphere for 60 seconds
Crafting an item will finish the quest and earn you the achievement.
If you are having any trouble with any other side quest, check out our full Dawnguard Walkthrough. It tells you everything that's new in the first expansion, including all the info on the new vampire options and guides for the main quest and major side quests.