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