Here is the full list of all 29 INMOST achievements.
Zero deaths as the wanderer.
Play without collecting any pain.
Gain all the achievements.
Talk to the cats when their sibling is dead.
Kill all enemies as the Knight.
Complete the Slime Pit scene without taking damage.
Complete the swamp scene without taking damage.
Complete the fire scene without taking damage.
Complete the castle scene without taking damage.
Collect all the Pain Crystals.
Find all the notes.
Listen to all the rabbit's comments.
Talk to the cats when their sibling is alive.
Listen to all the Storyteller's tales.
Kill all jumpers.
Finish the final scene.
Complete the Snow scene without taking damage.
Discover what's in the attic.
Discover the fountain.
Host a Tea Party!
Get the Cookies.
Enter the mines.
Find the rabbit.
Listen to the Storyteller's first tale.
Defeat the first hunter.
Finish the Old Man Scene
Save the cat from the hunter
Find a hidden Pain Crystal
Finish the Girl Scene