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