Here is the full list of all 38 Moss achievements.
Collect all of the forgotten fragments.
Collect all of the Relic Dust.
Finish the first book of Moss.
Defeat the serpent Sarffog.
Climb to the castle bridge alongside Quill.
Break everything within the town pub that can be broken.
Collect a large amount of Relic Dust.
Annoy Quill by delaying the adventure.
Startle Quill from behind.
Enter the Abandoned City alongside Quill.
Destroy a Forged enemy with an aerial attack.
Enter the Namelhook Mining cave alongside Quill.
Guide Quill to destroy multiple thorn patches.
Use Quill's sword to cut down a lot of grass.
Destroy a Forged enemy with a controlled Scorcher.
Use your power as a Reader to break many objects.
Unlock the path to the Mire Temple's altar room.
Light the torches of the Knights of the Sun.
Collect a small amount of Relic Dust.
Take control over many Forged enemies.
Give Quill a high five.
Use a Screecher to unlock the path forward.
Enter the Mire Temple alongside Quill.
Defeat the Screechers first encountered in the Mire.
Use your power as a Reader to heal Quill for the first time.
Discover your first Forgotten Piece.
Enter the Clearing alongside Quill.
Follow the Starthing and Quill into the impassable Mire.
Find a low-hanging path to the town pub.
Destroy two or more Screecher enemies with a controlled Ticker.
Rescue Argus without a single death.