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