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