I'd go with Last Ninja: The Dungeons, with that eerie C64 soundtrack.

The Ocean House Hotel Level in Bloodlines
Several levels in Clive Barkers undying

Ultimate Doom E2M4: Deimos Lab and E2M6: Halls of the Damned. Very dark for the most part - and the evil Barons of Hell (yes I know how to fight them now, but they're still a handful 😵 ).

Unreal Map 36 - The Darkening. Incredibly dark, even the Searchlight is barely enough to see where you're going. And those luminescent Skaarj that just refuse to die 😖

Thief III? 🤣 I was once scared by Thief 1. particularly when those damn zombies come into play

it may sound silly now, but this was way before the horde of zombie games.

also shock2 was once scary, and so was AvP before 'gold' ruined it all

Not exactly scary, but Thief 1's level on the Cathedral was certainly tense and uneasy.

I too found System Shock 2 to be rather scary at times. I remember going through a set of rooms situated on a catwalk, looking for supplies or whatever and as I was coming out from each room I would lean out first to check if anybody was around. This was a great recipe to shit my pants as the one time I did that an enemy was behind me, and as soon as he spotted me started shouting "Kill me!". I seriously almost fell of my chair.

Scratches is an amazing adventure game that kept me on the edge as well. There are two particular moments that always spring to mind, the first one would have to be the one with the mask and then the other one the cellar/boiler room scare. Thankfully, I wasn't playing late at night as I would have been unable to sleep. Those who have played the game will surely know what I am talking about.

As a child, I remember being very scared of Half-Life and Soul Reaver's main menu of all things. For those of you that don't know/remember, the main menu in Soul Reaver had about 7 statues that would turn around and look towards the screen with demonic faces at random. Here it is just for reference:
https://www.youtube.com/watch?v=z_1U-wVU488

More recently, I played through The Lost Crown with my girlfriend which had quite a few legitimate scares. It scared the living crap out of us on a number of occasions, to the point where I think I would have been unable to finish it on my own.

A couple of the levels as marine while playing AVP2 surely scared the shit outa me 🙁
Constantly turning around, waiting for the motion tracker to ping...it was awesome! 😁

Tetrium wrote:

A couple of the levels as marine while playing AVP2 surely scared the shit outa me 🙁
Constantly turning around, waiting for the motion tracker to ping...it was awesome! 😁

+1 for AGP. That soundtrack, the motion tracker, the flickering lights, darkened room - most scared I have ever been during a game.

Also those spider things in Half Life 2 that jump into your face - terrifying!

Anything involving Burricks or Zombies on Thief. Super-dread right there.

Also, Diablo 2, Act 2, THAT boss. Not as scary as it is "oh god is he going to kill me instantly this time?"

*** System Shock 2 ***

This is the main reason I'm playing it again after all these years... when I was young, I was too afraid and uninstalled it after one of those mutants appeared just in front on me while I was turning... great atmosphere. I hope to finish it this time: it deserve this.

Stalker SOC, the underground level in that factory.

Davros wrote:

The Ocean House Hotel Level in Bloodlines

I'm with ya, what a great level.

DOOM 3 had some very creepy, claustrophobic levels too.

System Shock 2 where you had to go through the parts where "the many" had transformed the ship and there were sphincter like doors.. that freaked me the heck out

But then Freddy Kreuger used to freak me out too.. and now it's all meh

"That's the old passage to Ravenholm. We don't go there anymore..."

The end of ski free with that bastard snowman thing with the yellow teeth comes to eat you up.

C64-Amazon
The first time you see the Huni come into the monitor.
Enough to scare the 5 year old me for years.

Even though I don't find anything in the game remotely scary anymore, the opening music still makes the hair on the back of my neck straighten, almost like it's this deeply rooted survival response...I just shrug it off and keep playing.

This scared me back then on Atari 800XL when I played it for the first time and had no idea 😉
https://www.youtube.com/watch?v=BK3Ti99IEF0

kixs wrote:

This scared me back then on Atari 800XL when I played it for the first time and had no idea 😉
https://www.youtube.com/watch?v=BK3Ti99IEF0

I'm dying. That was hilarious!

I'll add a video as well then: https://youtu.be/Ek2xE8SgyxU
That SID, so beautifully eerie.

kixs wrote:

This scared me back then on Atari 800XL when I played it for the first time and had no idea 😉
https://www.youtube.com/watch?v=BK3Ti99IEF0

🤣 his Maniac Mansion cameo also made me jump then