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