Here is the full list of all 30 Battle Princess Madelyn achievements.
Defeated the heart of the eel!
You've defeated the Crab Mini boss!
Defeated the zombie boar!
You've collected 5000 gold pieces.
You've released 15 spirits!
Crushed the evil witch sisters!
Found your first Doll!
You've released your first spirit from it's shackles!
Beat the kings guard! Now you have a map to continue your journey!
You've killed 100 enemies!
Get eaten by the tentacle monsters
Defeated the evil tree!
Defeated a mutated Max!
Defeated the fart troll!
Defeated Undead Nuburu!
Defeat giant toy rabbit!
Fritzy eats the wizards head!
Defeat the evil sorceress!
You've killed 1000 enemies!
You've killed 2500 enemies!
You've collected 20000 gold pieces.
You've collected 100,000 gold pieces.
You've released all spirits!
You've found half the dolls!
You've found all of the dolls!
You've unlocked the hidden level!
You've completed Stitch Bot!
Collected all of the runes for Fritzy to unlock the gates to the ruins!
Finished Arcade Mode!
Collect the Maddi doll, you've got your face in a game Maddi!