Here is the full list of all 20 Abyss: The Wraiths of Eden achievements. It takes around 6-8 hours to unlock all of the achievements on Windows.
Scare the beast blocking your way
Collect the Flower from Greenhouse
Give a cute squirrel a nut
Finish any hidden-object scene with less than 5 misclicks
Free yourself from the Restraining Vines
Finish any hidden-object scene in less than 1 minute
Make your way through the maze in the Agricultural section
Finish 3 hidden-object scenes in a row without using any hints
Finish 3 mini-games in a row without using the Skip button
Find 3 hidden-objects within 3 seconds
Finish any mini-game in less than 1 minute
Finish all the mini-games without using the 'SKIP' option
Finish all hidden-object scenes without using any hints
Finish a game of Domino in less than 1 minute
Finish half of all the games of Domino
Finish all the games of Domino
Escape from the Laboratory
Complete the game (Expert Mode)
Save your child from the hospital (additional content)
Unlock all the Achievements