Complete the following tasks to unlock the corresponding achievement. To view your achievements and stats in Steam, select "Community", then "My profile", then "View all my games", then the game and view stats.

Achievement	How to unlock
A Lich to Scratch	Defeat the Overseer.
Angler	Catch 50 fish.
Beast of Burden	Fill your pet's inventory.
Beast Slayer I	Defeat ordrak on easy or normal.
Beast Slayer II	Defeat Ordrak on hard.
Beast Slayer III	Defeat Ordrak on very hard.
Big and Green and Dead all Over	Defeat Krag.
Bum Luck	Have an item disenchanted on the first enchantment attempt.
Cash for Trash	Sell 10,000 items to vendors.
Deep Delver	Reach the 50th floor of a dungeon.
Deep Pockets	Have 100,000 gold in your inventory.
Down the Hatch	Complete 50 hatch quests.
Enchanted	Successfully enchant one item 5 times.
Enchantment Overload	Successfully enchant one item 10 times.
Epic Strike	Do at least 10,000 damage to an enemy in a single strike.
Fetch a Fair Price	Send your pet to town.
Fisher King	Catch 1000 fish.
Fisherman	Catch 100 fish.
Gambling Addict	Gamble 50 times.
Gambling Enthusiast	Gamble 20 times.
Gambling Fiend	Gamble 100 times.
Gibbed	Blow 25 enemies to pieces with critical strikes.
Hardcore Champion	Defeat Ordrak on hard hardcore.
Hardcore God	Defeat Ordrak on very hard hardcore.
Hardcore Hero	Defeat Ordrak on normal hardcore.
Hardcore Victor	Defeat Ordrak on easy hardcore.
Hat Trick	Beat the game with all three classes.
Ironman Victory	Defeat Ordrak without buying anything.
Ka-Chunk!	Pull 100 levers.
Line of Kings	Retire over 300 levels worth of characters.
Lucky Gambler	Gamble a unique item.
Master Smasher	Smash 1500 Breakables.
Mod Maniac	5 mods installed at the same time.
Mod Squad	1 game mod installed.
Modpocalypse	10 mods used at the same time.
Noble Lineage	Retire two characters.
Only a Master of Evil	Defeat Alric.
Over the Brink	Defeat Brink.
Passing the Torch	Retire a character.
Pension Plan	Achieve player level 65.
Perfect Victory	Defeat Ordrak with no deaths.
Pet Trainer	Equip a spell on your pet.
Potion Whiz	Drink 5,000 potions.
Price of Loyalty	Use 50 potions on your pet.
Purple People Defeater	Defeat Medea.
Questor	Complete 200 Quests.
Rich	Collect 250,000 gold.
Shape-Shifter	Change your pet by feeding it fish.
Sir Mixes-a-lot	Successfully create 25 items using the transmuter.
Sorcelator's Servant	Transform your pet into a Mimic.
Speed King	Defeat Ordrak in less than 5 hours.
Superstar	Achieve maximum fame.
Supreme Slayer	Kill 50,000 monsters.
Swift Execution	Defeat Ordrak in 8 hours or less.
The Adventure Begins	Find the entrance to the mine.
The Horse Whisperer	Achieved enlightenment by speaking with the horse 100 times.
The Long Haul	Achieve player level 100.
The Need for Greed	Suffer 20 disenchants from the enchanter.
Tormented	Die 500 times.
Transmogrifier	Permanently transform your pet.
Tree Hugger	Defeat the root golem.
Trolling for Punishment	Kill 25 champion trolls.
True Delver	Reach level 100.
Universally Understood	Complete 25 Gar quests.
Wabam!	Kill 5000 Monsters.
Walkabout	Take 25,000 steps.
When this Town's a Rockin'	Defeat the Ember Colossus.