How To Unlock: Complete "Darkness Returns".
For the second Thieves Guild achievement, you’ll have to take part in a few Thieves Guild jobs first. The following are missions required for this achievement:
- Loud and Clear - A nice little heist job of sorts.
- Dampened Spirits - Someone wants you to do some of their dirty work.
- Speaking With Silence - Head into the dark depths of the Snow Veil Sanctum.
- Hard Answers - Head to Winterhold and beyond.
- Darkness Returns – The less said, the better, just complete this quest.
- The Pursuit – Head back to the thieves guild and begin this new quest.
- Trinity Restored – Take a trip to get something of great power.
- Blindsighted – Travel somewhere and get something important.
- Darkness Returns – Finish it, once and for all.