Here is the full list of all 30 Phantom Path achievements.
Obtain the lantern.
Survive an encounter.
Get hurt by a trap and stay alive.
Exit an area while carrying fire.
Obtain the phantom stone.
Obtain both arcane keys.
Create a power module.
Find a secret area.
Find every secret area.
Obtain an arcane book.
Obtain all arcane books.
Scare the weird critter 20 times.
Attempt to ride a sheep.
Enter the city.
Enter the temple.
Enter the unknown.
Find some treasure.
Find a lot of treasure.
Find all the treasure.
Obtain the ultimate treasure.
Pop 20 flowers.
Obtain all the knowledge for your journal.
Reach the bad ending.
Reach the worst ending.
Reach the neutral ending.
Reach the good ending.
Reach the best ending.
Reach the secret ending.
Reach the secret (good) ending.
Reach the secret (best) ending.