Here is the full list of all 40 Archvale achievements.
Collect every badge.
Complete every trial.
Defeat the Old King.
Reconstruct the gateway to Archvale.
Obtain Avarn's Sword.
Collect all healing flasks.
Collect all Heart Containers.
Defeat the Banished Executioner.
Assemble the Arch Lexicon.
Craft 30 items.
Defeat the Colossal Skullbot.
Equip a shark cap and mermaid tail.
Store over 10,000 gold in the bank.
Survive the ritual of the Molten Rift.
Obtain the best potion recipe.
Defeat the Sunken Queen.
Cash in 10 treasures.
Defeat the Grove's Blight.
Destroy the barrier guarding Tanglegrove.
Defeat the Rotted King.
Complete half of your badge collection.
Defeat Frankenslime.
Defeat the Exiled Wizard.
Defeat the Fallen Pharaoh.
Defeat 1000 enemies.
Own 8 hearts.
Defeat the Queen Duneworm.
Defeat the Soul Serpent.
Enter the Twisted Caverns.
Defeat the Ghost Crab.
Fully upgrade a weapon.
Restore 10 fountains.
Defeat Mongo.
Obtain an improved healing recipe.
Defeat the Great Slime.
Complete your first trial.
Defeat Maxilla.
Die.
Find the village of Timberwell.
Perform five consecutive dashes without stamina recharging.