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