Here is the full list of all 28 Dungeon Punks achievements.
Reach experience level 20
Defeat a total of 4800 monsters
Complete Chapter 9: The Shrinewood
Accept and complete 50% of all missions
Complete Chapter 8: Riptide Beach
Complete Chapter 7: Forest Laboratory
Upgrade all hero spells to Rank 2
Defeat a total of 2400 monsters
Complete Chapter 6: Abandoned Crystal Mines
Complete Chapter 5: Goblin Slums
Recruit all six heroes
Reach experience level 10
Complete Chapter 4: The Floating Isles
Defeat a total of 1200 monsters
Complete Chapter 3: Voleglade Village
Defeat a total of 600 monsters
Defeat a total of 300 monsters
Complete Chapter 2: Sedge Dale
Defeat a total of 150 monsters
Complete Chapter 1: Thorian Palace
Complete Chapter 10: Drakken Badlands
Complete Chapter 11: Gas Swamps
Complete Chapter 12: The Nether Realm
Beat campaign on New Game+ mode
Learn all hero spells at Rank 1
Accept and complete 75% of all missions
Accept and complete 100% of all missions
Reach experience level 40