Here is the full list of all 24 Princess.Loot.Pixel.Again achievements. It takes around 20-25 hours to unlock all of the achievements on Windows.
Make a party!
Collect 3000G in one run
Get Rank C
Make four deals with the cat in one run
Collect 46 artifacts
Paladin saves King
Necromancer saves King
Rogue saves King
Archer saves King
Berserk saves King
Collect 15 artifacts in one run
Mage saves King
Collect 23 artifacts
Find baby
Candlevania!
Explode the door
Press TAB in the main menu
Warrior saves King
Get Rank S
Get Rank A
Find hidden place
Get Rank B
Die for the first time
Start main Quest