Here is the full list of all 16 LEAVES - there are The Return achievements.
Didn't need any help
Played the game without interruption
Found 15 inhabitants
Niche4 puzzle solved
Solved the hand puzzle
Pfeffersack sleeps at the noses
Found 10 inhabitants
Gave Pfeffersack the salad
Used the Travelstone 3 times
Found 5 inhabitants
Opened the portal
Opened the underground
Solved the electric puzzle
Collected 3 drops
Found the magnifier
Upset the Treefruities