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