Here is the full list of all 15 Heroes of Loot achievements.
Kill a minotaur
Drink from the well
Maximise dungeon difficulty
Become level 10
Activate a statue
Reach dungeon level 15
Buy a titanium shield
Become invisible
Kill a cyclops
Play in the Arena room
Save a lost soul
Upgrade the difficulty of the dungeon
Get the "Lens of secret"
Slay 5000 monsters
Unlocked Barbarian character