Here is the full list of all 18 Turn off the light achievements.
Go down to the strange basement by elevator
Talking to a Stranger
To die for the first time
Use antidepressants
Achieve a friendly relationship with a Stranger
Maintain a neutral relationship with a Stranger
Achieve a negative relationship with a Stranger
Collect all the pictures
Stop the steam supply in the tube
Release the elevator from the trolley
Check the vending machine
Yes, you?
The secret ending
The good ending
The bad ending
Successful escape
Find out everything that the Stranger was talking about
Use the Purification Totem