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