Vanilla-ish/ambient horror mods

Hello everybody

I'm sorry if this gets posted often, I tried to do a search but didn't exactly find what I was looking for

I am searching for horror mods that fit a couple of criteria

• isn't the main focus of gameplay and draw all attention to itself constantly
• fits generally well within the vanilla framework
• isn't just a flat .png monster
• doesn't break my house down
• provides mostly ambience rather than a huge challenge
• isn't constantly "happening" but has the spooks as a relatively rare occurence

Hopefully someone understands the general vibe I'm going for and can help

Thanks in advance!