Here is the full list of all 16 Midnight Mysteries 3: Devil on the Mississippi achievements.
Complete each HOG in Story Mode without the lantern.
Collect 100 clovers in Story Mode.
Find all the boats in Deptford without a miss.
Find every hidden object in all Unlimited HO Mode scenes.
Complete the bonus chapter.
Solve all the puzzles in Story Mode.
Complete Story Mode without using any hints.
Collect all the ravens in Story Mode.
Unlock Unlimited Hidden Object Mode.
Complete a hidden object scene in less than a minute in Story mode.
Find all of them 80 bones in "Dem Bones."
Complete Story Mode.
Complete Story Mode with no Black Cat scares.
Clear the pool table in one shot.
Complete the Captain's lock puzzle.
Collect the skull from Joe.