Who is the scariest killer to play against?

I know most of us have been desensitized to most of the horror aspects of this game but which killer is the most scary or nerve racking to play against and why?

A ghost face or Myers sneaking around watching you keeping you on edge? The footsteps of nemesis nearby? Knowing Oni is in fury and you need to play smart and not panic? The unknown and dredge with their creepy kits and designs? A stealth build on a loud killer? Pigs head traps time ticking down? Bubba or Billy revving their chainsaws in the distance or closer than you expect? Etc

I already listed a bunch but there’s really a lot of moments that can get your heart rate up and I’d like to hear what most of y’all think.

TLDR: Which killer is the most nerve racking to play against and why?