Portal isn’t exactly scary, but it is creepy, in a psychological sort of way. Or at least, GladDOS is, but she rather pervades the game.
Another psychological entry is Alice. I’ve never played it, but what I’ve seen convinces me that if the game isn’t set entirely in a mental institution, it should be.
The original Diablo had great ambiance. The gameplay is far superior in the original, but it doesn’t have anywhere near the ambiance the original did.
And for ghosts-behaving-ghostily, the “Ibis Crown” level of Myth II, set in the haunted catacombs of Muirthemne, is great. Some of them are enemies, some are allies, some are enemies of your enemies but still enemies to you, and some are apparently completely oblivious to your presence, and they all fade in and out, or come out of nowhere, or run straight through walls, or the like.
Well, Alice is in a mental institution after a fire burned down her home and killed her parents. The entire game is her going back to wonderland, suitably twisted in her now twisted mind.
I LOVED Manhunt. I thought it was creepy and scary. Really creepy. Widely panned (I think XBox mag gave it a 4.5 based on the “disgusting” content) and even banned in some places but I thought it was AWESOME! Based on the idea of snuff films and reminiscent of the movie The Warriors, you must make your way through various areas using whatever materials are available (like plastic bags) to defeat the local psychos.
And - The Suffering. A haunted prison on an island off the coast of Maryland? Are you kidding me? Brilliant. Also creepy and scary! Very mature content.
I also loved Eternal Darkness - in my opinion the best console game I’ve ever played (easily the best thing available on the GameCube), and the only time I’ve seen a game make a decent stab at a Lovecraftian theme.
The sanity meter is a nice touch - in addition to health and mana you also have sanity - when this depletes, strange things begin to happen. You might walk into a room and find yourself walking on the ceiling, or your head might suddenly explode, or you find yourself turned into a zombie - in each case after just enough time to get you properly bemused things suddenly switch back to normal.
My favourite was the random pop up of a screen telling you that you’d completed the game and to wait for the sequel, which confused me no end the first time it appeared.
The “insanity” effects were brilliant–it was almost worth letting your character’s sanity meter deplete just to see what kind of weird shit would pop up. One of my favorites was when it starts to look like flies are crawling around on the inside of the TV screen.
The funniest one I saw, though, was suddenly having a green “VOLUME” bar appear onscreen and rapidly drop to zero. My friend thought he had sat on the TV remote and jumped off the couch.
Shellshock II for the PS3. My wife was having nightmares, and had to give it up. I finished it, and thought it was a fun game, and gets high marks on the scary meter.
I only saw it once, but I swear that game cause a fake reboot of the Gamecube, only it loaded as a Sony Playstation 2 for second, before the gag was revealed.
I see it listed in the sanity gamefaq on gamefaqs, but others have told me they didn’t see this effect. I had a first printing of the game. Don’t know if that matters.