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