Look for morphing coral and hidden crabs in every scene. Missing items can be picked up in the "Extras" section after finishing the game.
If you prefer visual guides, YourGibs Gaming and AdventureGameFan8 offer comprehensive video playlists covering the full game and bonus content. Mystery.Case.Files.Black.Crown.CE.rar
These are multi-part puzzles. You must complete one section to unlock the next, though you can skip individual parts if needed. Look for morphing coral and hidden crabs in every scene
This gadget is used frequently to reveal hidden details or progress through puzzles. Puzzles & Hidden Object Scenes (HOS): Mystery.Case.Files.Black.Crown.CE.rar
Some scenes blend puzzles with hidden object lists; be prepared to interact with objects (e.g., using a corkscrew or bayonet) to find required items. Collector's Edition Extras