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