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