Here is the full list of all 42 Knights of Pen and Paper +1 achievements. It takes around 20-25 hours to unlock all of the achievements on Windows.
Finish the storyline as fast as you can (less than 365 days but you may extend that to 465).
Clear 50 dungeons.
Clear 10 dungeons.
Buy all goodies in game.
Buy the highest weapon upgrade available.
Play with all characters in game.
Buy the highest armor upgrade available.
We know it may be frustrating to die so we've just rewarded you with this achievement. Do not give up, the game is about to begin!
Visit every single place in game.
Play with all classes in game.
Complete a campaign using all 5 Game Developers as characters.
Reach Level 15 in a specific Spell.
Unlock all masters.
Choose a weird combination of character and class.
Continue the game after a game over.
Visit your Kitchen inside the game.
Kill a dragon.
Finished the campaign.
Clear a dungeon.
Unlock a new master.
Reach Level 30 in every character of your group.
Spend 9.001 golds.
Earn 9.001 golds.
Reach Level 30 in a trio.
Reach Level 30 in any character.
Use a potion while full health.
Unlock the Necromancer class.
Unlock the Shaman class.
Unlock the Bard class.
Unlock the Knight class.
Unlock the Game Developers that made the game.
Unlock the Barbarian class.
Unlock the Hunter class.
Reach Level 15 in any character.
Roll 20 in any random roll.
Gather 10 grindstones from veins.
Make the blacksmith dance.
Win a battle with 7 monsters.
Roll 1 in any random roll.
Kill an elite minion.
Gather a grindstone by mining veins.
Reach Level 5 in any character.