Here is the full list of all 44 Shantae and the Pirate's Curse achievements. It takes around 20-25 hours to unlock all of the achievements on Windows.
Saved Scuttle Town as fast as possible!
Defeated the Pirate Master's true form without taking any damage.
Destroy 20 bones with the Bubble Shield.
Defeat the Pirate Master's true form and save Scuttle Town in record time!
Defeated the Steel Maggot without taking damage.
Play keep away with the Ammo Baron.
Defeated Dagron without taking damage.
Defeated the Squid Baron without taking damage.
Defeated the Empress Spider without taking damage.
Defeated the Cyclops Plant without taking damage.
Defeated the Cyclops Plant using only Pike Balls.
Defeated the Ammo Baron without taking any damage.
Complete the hidden training room.
Discover the secret Labyrinth.
Complete the game without any Health upgrades and all Heart Squids collected.
Defeat the Pirate Master's true form.
Collect all Heart Squids.
Defeated the Pirate Master without taking damage.
Defeated the Pirate Master.
Collect all of the Dark Magic.
Defeated the Steel Maggot.
Collect all Labyrinth maps.
Help Ammo Baron fire the Palace Disruptor Cannon.
Collect 50% of the Dark Magic.
Collect the Enchanted Blade.
Obtain the Spirit from Abner.
Defeated Dagron.
Sample the entire menu!
Collect 50% of the Heart Squids.
Obtain Manly Musk.
Obtain the Fossil.
Defeat 50 enemies using Pirate Weapons.
Defeated the Squid Baron.
Obtain the Golden Pickaxe.
Obtain all three Mummy Sketches.
Defeated the Empress Spider.
Destroy 10 Spider Eggs before they hatch.
Get Rottytops to Abner Tree without making any mistakes in a single attempt.
Defeat 250 enemies using Shantae's Monster Whipper!
Obtain Squid Oil.
Defeated the Cyclops Plant.
Release the Ham Stink.
Use a Pirate Flare to return to Risky's ship.
Defeated the Ammo Baron.