Movie monsters/creations that are pure nightmare fuel

[Steedeel]

As the title says, which creations did you find the most terrifying?

My top 5

Xenomorphs (Alien)
Stunningly designed, almost mechanical with a dome shaped head and another set of jaws when needed, a creature that bleeds acid and is relentless in their aim of using humans as a incubator in their early lifecycle phase, by attaching themselves to the target’s face, and at the right time, bursting from the host’s chest. In any form, pretty terrifying stuff.

Pod People (Bodysnatchers)
Whichever version you prefer (1978 for me) the idea of an otherworldly threat that can replace a human being in form but not personality is pure nightmare fuel. Paranoia and suspicion, matched with the terrifying thought that you or loved ones can be present without being their old selves is surely a metaphor for a real world threat such as dementia, and it’s all the more terrifying for it.

Pennywise (I.T)
An alien that can take many forms is scary enough, however one that can feed on children’s fears and become that fear is a terrifying thought. An alien that can emotionally manipulate a child, for the purpose of devouring them eventually, well as a child watching the tv series (counts as a film now due to remake of course) it really plays into our imagination and forces us to question our own fears and where they come from.
Of all the forms the alien takes, it’s the clown that steals it for me personally.

Bob (Twin Peaks/Fire Walk With Me
Bob, the entity that feeds on fear and sorrow, stalks and torments Laura Palmer throughout her life, leading to tragedy and a town that will never be the same again. I’m sure most of us know the backstory and more recently, the origins, for me, it’s the idea that a force exists purely to cause emotional pain and sorrow to a whole community, let alone ultimately death is nightmare fuel.
Add to that, the terrifying ‘lodge’ happenings, and I just don’t think it’s gets more terrifying than that.

Running bomb (The Creator)
A much more recent entry, the idea of a robot designed for one reason, and one reason alone, to find a target, chase that target, then detonate is chilling. The fact is looks like a bulky garbage can with arms and legs doesn’t take away from that fear, with the robot able to barge through people to reach its target. Terrifying, and it just steals the glory from the far more complicated but brilliant T1000 in T2, the superior film by far, but we are talking individual creatures/creations here!

There are hundreds more, but that’s my top five.

Would love to see yours, with a short explanation why.