Can we stop with the bashing?

Okay, OP. Honestly, Minecraft isn't the game at all for jumpscares, and I mean at all. Unless someone had created a mod for you that made jumpscares appear on your whole screen, but I don't think there is any way at all to do what you want to do.

Sincerely,
Volt/Liam.

I was reading through my little brother's pre-primary school graduation, and a 6-year-old girl put Five Nights at Freddy's as her favourite game... just saying...

1.ok there is a way you could do something like this but you will need to create a custom resource pack yourself and have the users download it with the map.
useing this you could do a few things such as use custom textures and custom sounds.

2*I think the easiest way, though im not sure it would work would be to use a picture to map conversion tool or plugin to turn any picture into a wall of maps and then use command blocks to clone a wall with the picture on it wherever needed and the have it delete the wall after a short time.(you could also have it play your custom resource sounds for a scream or something)*

Great, another FNAF fanboy.

Thanks, I've seen that too. LogdotZip I think

I remember seeing a video on how to make a jumpscare contraption in MC, however, I don't think it's really something for FNaF.