Full list of all 52 Investigator achievements.
The base game contains 34 achievements, and there is 1 DLC pack containing 18 achievements.
Find six gnomes in DLC
Do not kill Steve
Kill Steve
Get in the face
Complete the tenth level
Play the guitar
Burn on a hot plate
Find the gnome on 10 level
Find the saw room
Complete the ninth level
Complete the eighth level
Complete the seventh level
Make a snowman
Collect five gnomes in the seventh location
Fall through the Ice
Complete the sixth level
4 8 15 16 23 42
Complete the fifth level
Complete the fourth level
Try to get away from Johnny
Complete the third level
Explore the plane
Find the gnome at the third location
Kill the spider
Dial pockets full of garbage
Complete the first level
Find the gnome in the toilet
Kick the ball into the goal
Warmed by the fire
Push the barrel into the water
Complete the second level
Do not kill spider
You are bitten by a spider at the sixth location
Play the game
Play "Survivor Update"
Find five balls in "Survivor Update"
Find Artifact in "Survivor Update"
Find second Artifact in "Survivor Update"
You were eaten! "Survivor Update"
The way "Survivor Update"
Too slow! "Survivor Update"
Find a suitcase with achievements "Survivor Update"
Find a can of fuel "Survivor Update"
Look where you're going! This is not Assassin Creed "Survivor Update"
Find the hidden achievement on the fifth level "Survivor Update"
Finish "Survivor Update"
Find new shoes