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