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