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