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