My scariest moment happened when I played "The Box of Horrors" Mod:
If you played the mod and if you remember, that there is a Medibay room, then hopefully you probably remember that there is a zombie in that room.
As I remember there was a bug which gave me a heart attack (some players had this moment as well

). We know that zombies can't open doors, but that zombie could walk thought the door (without opening it) only when player is not looking.
Basically, when I entered a storage, 106 began to appear. But when I turned around, I saw that zombie which gave me that *@$*Y#@% heart attack because the zombie didn't make any sound. I know these words doesn't sound too scary, but hopefully you know this feeling (and no, I am not fearful).
I also remember that I was jumpscared when I entered 372's room and when SCP-173 killed me. I was scared just because usually 173 is not there.

173 was just hiding in the corner. Son-of-a-
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