Full list of all 18 My Aunt is a Witch achievements worth 1,000 gamerscore. It takes around 1-2 hours to unlock all of the achievements on Xbox One.
Find All Skulls
Fail mini-game
Complete the mini-game on the first try
Cook a potion with Grimmor
Become Laura's Breakfast
Save the Bear
Become the enemy of the bears
Defeat the Banshee
Meet the Master of Fate
Visit Beatrice
Collect all the coins of Baron de la Pig
Find a lucky coin
Use dark magic on Elmara
Meet Elmara for the second time
Meet the doll from Silenced: the House
Outplay Malicente
Defeat a shadow girl in a battle of wits
Defeat the Spider