Full list of all 29 Nightmares from the Deep 2: The Sirens Call achievements. It takes around 8-10 hours to unlock all of the achievements on Windows.
Find all hidden octopi.
Finished 10 Hidden Object Puzzles in a row without any hints.
Find all morphing parrots.
Finished all Hidden Object Puzzles.
Finished all the puzzles without using the Skip button.
Finish all the games of Mahjong.
Find all secret seahorses.
Finish half of all the games of Mahjong.
Finished 5 puzzles in a row without using the Skip button.
Finish any Hidden Object scene with less than 3 misclicks.
Complete the game.
Got to the contents of Davy Jones' chest.
Gather twelve golden fish tokens.
Got to the top of the lighthouse and saw what's underneath.
Enabled your ally to return to work.
Prepare a spiked coffee.
Found your way inside the lighthouse.
Fix the radio.
Finished a Hidden Object Puzzle in less than 1 minute.
Enter the shipwreck cemetery.
Tried to get through the labyrinth without the map.
Find 4 Hidden Objects within 4 seconds.
Saved your ally from a tight spot.
Find a direct way to get behind the closed gates.
Visited a local bar.
Finish a game of Mahjong in less than 1 minute.
Finished a puzzle in less than 1 minute.
Witnessed the devastating attack of the sea monster.
Arrived on the pier.