Here is the full list of all 33 The Painscreek Killings achievements. It takes around 8-10 hours to unlock all of the achievements on Windows.
Truth Revealed
Matthew Brooks' Story
All Keys Found
Vivian Roberts' Story
Charles Roberts' Story
Best Friends Forever
Oliver Gibson's Story
All Tools Found
Sofia Miller's Story
All Newspaper Articles Found
Steve Moss' Story
Bloody Knife
Bernard Hopkin's Story
Wanda Tyler's Story
Here Lies Sofia
Scott Brooks' Story
Scott's Secrets
Trisha Roberts' Story
Derrick Tyler's Story
The Hidden Truth
The Secret Lies With Her
Andrew Reed's Story
Mary Martinez's Story
Guest's Lost Cap
Tutorial Completed
James Howard's Story
Dorothy Patterson's Story
All Letters Found
Completionist
Missing Journalist
Case Unsolved
You're Fired
Dying Man's Letter