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.
Visit your Kitchen inside the game.
Complete a campaign using all 5 Game Developers as characters.
Finished the campaign.
Reach Level 15 in a specific Spell.
Buy all goodies in game.
Play with all characters in game.
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!
Buy the highest weapon upgrade available.
Unlock all masters.
Visit every single place in game.
Buy the highest armor upgrade available.
Kill a dragon.
Reach Level 30 in any character.
Reach Level 30 in every character of your group.
Clear a dungeon.
Reach Level 30 in a trio.
Continue the game after a game over.
Spend 9.001 golds.
Earn 9.001 golds.
Choose a weird combination of character and class.
Unlock the Shaman class.
Play with all classes in game.
Unlock the Necromancer class.
Unlock a new master.
Gather 10 grindstones from veins.
Unlock the Knight class.
Unlock the Barbarian class.
Reach Level 15 in any character.
Unlock the Bard class.
Unlock the Hunter class.
Use a potion while full health.
Unlock the Game Developers that made the game.
Make the blacksmith dance.
Roll 20 in any random roll.
Roll 1 in any random roll.
Win a battle with 7 monsters.
Reach Level 5 in any character.
Gather a grindstone by mining veins.
Kill an elite minion.
Finish the storyline as fast as you can (less than 365 days but you may extend that to 465).
Clear 10 dungeons.
Clear 50 dungeons.