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