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