Here is the full list of all 24 LUNA The Shadow Dust achievements.
To light a candle is to cast a shadow
Water the tree over 20 times
Triggered stone form for both characters
Üri reunited with Layh
Travel back to the tower
Master and I
Bounce on the bed over 20 times
Layh dropped over 30 times during the game
Üri met Layh
Reveal all four paintings
Enter the tower
Go through doors over 20 times in the Moon Painting Room
Complete the Moon Painting Room with no mistakes
Send Layh through the tube
Experienced all food cooking combinations
Reach the exit in shadow form without dropping once
Finish listening to the whole performance
Release the bee in all four seasons
Select the wrong book
Travel back to the room
Complete the dark wheel jigsaw
Reach the top of the ladder without slipping once
Discover the hidden island
Met the new apprentice