Here is the full list of all 30 The Dark Pictures Anthology: Man of Medan achievements.
Unlocked Conrad's Humorous Trait
Found all Secrets!
Found all Pictures
Found all of the black framed Pictures
Only the men survived!
Finished Movie Night
Chose all of the Heart decisions
Unlocked Julia's Spoilt Trait
Maxed Conrad and Fliss's Relationship
Completed the Solo Story
Only the women survived!
Chose all of the Head decisions
Found all of the white framed Pictures
Unlocked Fliss's Arrogant Trait
Conrad successfully flirted with Fliss
Opened the window without making noise
No-one survived!
Everybody survived!
Calmed Junior down
Revealed the name of the ship
Found 25 Secrets!
Unlocked Alex's Aggressive Trait
Maxed Brad and Alex's Relationship
Julia accepted Alex's proposal
Finished the Shared Story
Maxed Alex and Julia's Relationship
Conrad successfully escaped on the speedboat
Completed 10 QTEs in succession
Unlocked Brad's Envious Trait
Beat the Training Dummy