While their purpose remains unknown, the city-states were undefeatable, and held their ground against attacking Nords for centuries. In ancient times, the Dwemer constructed four city-states, led by the great research center of Arkngthamz in the Reach. Choose your reward: the Aetherial Crown, Aetherial Shield, or Aetherial Staff.Locate the Aetherium Forge inside the Ruins of Bthalft.Locate and retrieve the four Aetherium Shards.(Optional) Retrieve the unique bow Zephyr.With her help, I found the four Aetherium Shards that made up the key to the Forge, defeated its ancient guardians, and forged a powerful artifact. In Arkngthamz, I met Katria, a ghost searching for the mythical Aetherium Forge. With her help, I found the four Aetherium Shards that made up the key to the Forge, then defeated its ancient guardians. With her help, I found the four Aetherium Shards that made up the key to the Forge, then confronted its ancient guardians. With her help, I found the four Aetherium Shards that made up the key to the Forge, and combined them to reveal the entrance to a long-sealed ruin. With her help, I found the four Aetherium Shards that make up the key to the Forge, and met her outside its long-sealed entrance. With her help, I found the four Aetherium Shards that make up the key to the Forge, and now seek the entrance to the Forge itself. She left to search for the other shards and the Forge itself, and urged me to do the same. Together, we found one of the four Aetherium Shards that make up the key to the Forge. With her help, I solved the Tonal Lock that protected its ruined treasury and claimed the Aetherium Shard within. In Arkngthamz, I met Katria, the ghost of an adventurer who perished there. With her help, I solved the Tonal Lock that protected its ruined treasury and found a strange glowing crystal shard within. With her help, I solved the Tonal Lock that protected its ruined treasury. There, she warned me that the Treasury of Arkngthamz was sealed by a dangerous Tonal Lock and protected by deadly traps. We made our way through the ruins and reached the summit together. She warned me that the Treasury of Arkngthamz was sealed by a dangerous Tonal Lock and protected by deadly traps. She offered to join me in my fight to the summit, and I accepted her help.