Here is the full list of all 75 Lux, City of Secrets achievements.
Create a new character
Import a character who skipped 'Evertree Inn'
Import a character who skipped 'Sordwin'
Import a character who has visited both 'Evertree Inn' and 'Sordwin'
Open Case 1
Open Case 2
Open Case 3
Open Case 4
Open Case 5
Open Case 6
Open Case 7
Open Case 8
Chapter 1, Morning
Chapter 1, Afternoon
Chapter 1, Evening
Chapter 2, Morning
Chapter 2, Afternoon
Chapter 2, Evening
Chapter 2 or 3, Morning or Afternoon
Chapter 2 or 3, Evening
Chapter 3, Morning
Chapter 3, Morning or Afternoon
Chapter 3, Evening
Chapter 4, Morning
Chapter 4, Afternoon
Any Morning
Any Night
Epilogue