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