The only creature that has genuinely creeped me out were the wraiths in oblivion, and due to my paralyzing arachnophobia, giant frostbite spiders. Especially the sort that drop from the ceiling onto your head, i'm constantly looking up while i'm in a cave just to be sure i'm not gonna jump out of my skin. If I were on pc I would download that mod that replaces spiders with...bears I think it is?

. They wont be scared if they see monster from far. You can make spiders silently go behind player and loud TSSS voice when they start attacking.
Especially the headless ones... 
And boobs, of course
