Myers, Candyman, and Joe Spinell as Frank Zito / Maniac for me. Also the voice work in the Exorcist creeped me out as a kid.
For whatever reason, individual scenes affect me more than characters in horror films -
For instance, any eyeball violence -
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The train scene in Maniac screwed me up for a lot of years. I saw it when I was young, and my mom worked nights, so if she was ever late, my mind would flash on that scene -
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Scroll to 38:00 - 44:00. Still creeps me out sometimes

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Also the pull apart scene in Day of The Dead, but I got over it quick though. -
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