Here is the full list of all 30 Arietta of Spirits achievements.
Obtain the Spirit Sword.
Become a Bound.
Defeat the Wasp Queen.
Obtain the Wooden Sword.
Find Grandma's portrait.
Defeat the Huge Roamer.
Defeat the Spikeroot Roamer.
Defeat the Cloaked Roamer.
Defeat the Roamer Behemoth.
Defeat the Sunken Behemoth.
Get to keep Grandma's Silver Ring.
Find Minerva's hut.
Obtain the Herbicide.
Unlock the Spirit Shield.
Find Gibb's workshop.
Ladders finally fixed.
Complete the Journal.
Help Minerva cross over to the afterlife.
Escape from the Sunken Realm.
Complete the game.
Find all of Midri's goods.
Find all lost Spirit Cubs.
Unlock the Small Roamer Core.
Unlock the Medium Roamer Core.
Unlock the Large Roamer Core.
Help out Father in a sticky situation.
Pick blueberries for Mom.
Harvest all vegetables from the garden.
Kill a butterfly.
Complete the game on Extreme Mode.