Here is the full list of all 36 TUNIC achievements. It takes around 15-20 hours to unlock all of the achievements on Windows.
Found a certain weapon before getting a sword. (Page 38)
Made 15 wishes
Froze yourself
Found Secret Treasure #10
Found Secret Treasure #8
Found Secret Treasure #5
Found Secret Treasure #4
Found Secret Treasure #2
Completed the Manual
Found Secret Treasure #7
Found Secret Treasure #11
Found Secret Treasure #9
Had 10 moneybanks at once
Found Secret Treasure #6
Found Secret Treasure #1
Found Secret Treasure #3
Freed a friendly fairy
Found Secret Treasure #12
Found your rightful place
Restored corporeal form
Earned the Cathedral's Prize
Completed key collection
Found the red key
Found the blue key
Found the green key
Chopped down 1000 blades of grass
Understood the margin of page 17
Engaged a strange device
Rang the Western Bell
Made a wish
Made an offering
Perfectly executed a special technique
Rang the Eastern Bell
Was resurrected
Found a sword
Found a stick