What's a Monster you found Interesting or Terrifying?

[Mambi]

The Cenobites from Hellraiser! They have godlike powers over reality, but they only affect you if you call them, and they're not even evil.

Despite all that, their designs and their views on pleasure and pain being equal is absolutely terrifying to me. You can't negotiate or bargain with them, as they see their highly-calculated very intelligent torment as a blessing to guide you to their views on experience ("Who are you?" "Explorers, in the further regions of experience. Demons to some, angels to others.") The worst part is...if they do it right you eventually like it and join them no matter the horrors they inflict. ("...and to think, I hesitated!")

 

[TrixieFox]

Smiling Men from Marvels New Mutants

 

[Kinguyakki]

I was just rewatching season 2 of the Witcher, and the vampire girl in the first episode was creepy. Twitchy, crawling along the ceiling and walls like a bug. I wouldn't say it's terrifying, but it's unnerving and creepy to see a "human" or humanoid form move that way.

 

[Woozle]

It has been a while since I read Lovecraft, but I enjoyed the Shoggoths. They're just so freaky.