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