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