The Grim Reaper.
A type of serial killer who is employed as a caregiver and kills people under their care.
A shinigami.
An angel which attends to death, collecting souls at death, ending life at the appointed time of death.
Azrael.
Death, one of the Four Horsemen of the Apocalypse.
A night terror.
The action or quality of causing dread; terribleness, especially such qualities in narrative fiction.
Intense dread, fright, or fear.
Terrorism.
Something or someone that causes such fear.