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