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.
Collect 3000G in one run
Make four deals with the cat in one run
Get Rank C
Paladin saves King
Collect 46 artifacts
Rogue saves King
Archer saves King
Collect 15 artifacts in one run
Berserk saves King
Mage saves King
Necromancer saves King
Make a party!
Collect 23 artifacts
Warrior saves King
Press TAB in the main menu
Find baby
Candlevania!
Explode the door
Get Rank A
Get Rank S
Find hidden place
Get Rank B
Die for the first time
Start main Quest