Here is the full list of all 53 Puzzle Quest 2 achievements.
Defeat a Yeti after at least 100 turns have passed
Learn all the bonus spells
Defeat 5 opponents in multiplayer
Be defeated by an opponent on their first turn during single player quest mode
Defeat the Arch Lich
Watch the credits sequence to the end
Visit every room in the game
Choose the Bash mini-game whenever possible during the single player campaign
Complete the game
Gain access to Gorgons Cathedral
Complete the "Deep Delving Dwarf" quest
Advance to the Green Dragon in Endurance mode on full health
Survive the Endurance mode
Escape the Dark Dwarven Laboratory
Activate 5 traps during a campaign
Defeat the Green Dragon
Play the "Lucky Dip" side quest
Complete the "Insurance Fraud" quest
Do more than 250 damage during your turn
Forge the "Hammer of Righteousness"
Complete the "Imp!" quest for Crye
Pick your way through 5 locks
Magically force your way through 5 locks
Defeat an opponent on your first turn during any single player game mode
Kill an undead monster, then kill it again and again after it reanimates
Defeat Shadowbringer
Defeat the monster known as "Teh SkullBrekker"
Heal some trap damage by visiting Jarrum Blackstone in the Chapel
Make a match of 8 gems in a row in any battle game mode
Respec your hero by visiting Jarrum Blackstone in the Chapel
Complete the "Eye of the Owlbear" quest
Disarm 5 traps to avoid being wounded
Defeat an opponent while on 1 Life Point during any single player game mode
Search 5 rooms for hidden treasure or danger
Lose to an opponent who's on 1 Life Point during any single player game mode
Defeat King Godd
Bash your way through 5 locks
Defeat the Yeti
Upgrade an item to Epic
Complete the "Able Replacement" quest
Complete the "Stuff of Nightmares" quest
Upgrade an item
Clear the town of Goblins.
Defeat 500 monsters
Win 5 Tournaments
Defeat 1000 monsters
Defeat 2000 monsters
Finish the single player campaign with a hero from each class
Finish the single player campaign with both male and female from the one class
Complete the game without activating an item
Resist Subjugate or Crushing Kill
Win a Tournament with the first or second hero alive
Lose the burning inn challenge battle