Full list of all 11 Concealment achievements.
The base game contains 7 achievements, and there is 1 DLC pack containing 4 achievements.
Read the first letter.
Find the scull.
Find the bolt cutter.
Complete the story.
Face-to-face with the creature.
Create a detonator.
Kill the creature with an explosion.
Complete the game for a secret ending.
Complete the game for a bad ending.
Collect all the necessary things in the apartment.
Complete the game for a good ending.