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