Alarming
Appalling
Bloodcurdling
Captivating
Chilling
Creepy
daunting
disquieting
Disturbing
Eerie
Eldritch
Enrapturing
Enthralling
fearsome
Frightening
Ghastly
Ghostly
gloomy
harrowing
Haunting
Horrific
Horrifying
Hypnotic
intimidating
Macabre
menacing
Mesmerizing
Mystifying
Nightmarish
ominous
Otherworldly
Perturbing
Phantasmagoric
Phantom
scary
Shocking
Shuddering
Sinister
Spellbinding
Spine-chilling
Spine-Tingling
Supernatural
terrifying
threatening
Unearthly
Uneasy
unfriendly
Unnerving
Unsettling
Unworldly