Full list of all 19 9 Clues: The Secret of Serpent Creek achievements. It takes around 3-4 hours to unlock all of the achievements on Windows.
Complete all other achievements.
Solve all Puzzles without using the Skip button.
Find all Clues connected to your investigation.
Save yourself.
Find all nine
Complete all the Detective Mode scenes.
Gather information on all of the characters.
Solve three Lockpick puzzles in less than one minute.
Find five Clues connected to your investigation.
Watch the cutscene in the museum.
Solve five Puzzles without using the Skip button.
Get rid of Breebo for good.
Play with Breebo.
Read three newspapers.
Complete three Hidden-Object Puzzles without using the Hint button.
Find three Clues connected to your investigation.
Complete your first Detective Mode.
Solve a Puzzle without using the Skip button.
Finish your first Hidden-Object Puzzle.