Here is the full list of all 21 Occult achievements.
5 minutes to stand by the car
kill with train
big bang
mirror quest finished
defeat the evil
throw a friend out of the cupboard 5 times
kill mediums
killed the Spiderlady
open lockers and drawers 50 times
helped a friend get up
found the phone and answered the call
25 window jumps
first time stunned by a monster
start a four-player game
collected 10 jewelry
caught 25 spiders
died from the fall
complete the game alone
start a game together
sat in the closet for more than a minute
open 3 locked doors