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