Here is the full list of all 16 Unforgiving - A Northern Hymn achievements. It takes around 4-5 hours to unlock all of the achievements on Windows.
Max out the gamma slider
Drop 20 matches
Survive the Swedish forest
Survive the Swedish underworld
Find the Three Billy Goats Gruff
Die 10 times
Survive the Swedish woods without dying
Complete the Swedish underworld without dying
Complete the full game without dying
Find all of the treepeople and activate their dialogue
Unlock all the signs playing manually
Collect all the pages of poetry
Visit all the houses in the village
Find where it all began
Solve the puzzle and find the art
Clear all achievements