Here is the full list of all 16 I Expect You To Die 3: Cog in the Machine achievements.
Complete Level 6
Complete Level 5
Complete Level 4
Complete Level 3
Complete Level 2
Complete Level 1
Open the mysterious vault
Find all hidden statuettes
Complete all level speedruns
Complete all side objectives on Level 1
Complete all side objectives on Level 2
Complete all side objectives on Level 3
Complete all side objectives on Level 4
Complete all side objectives on Level 5
Complete all side objectives on Level 6
Complete all levels under the speedrun time, find all hidden statuettes, and discover all souvenirs