For raw unrelenting atmosphere System Shock 2 was pretty bleak and I definately agree with you on the weapons point. The beginning of the game when armed only with a wrench as mutated wretches drag themselves towards you down the corridor begging you to kill them was terrifying to me back in 1999.
The Thief 3 level The Cradle and the haunted mansion in Vampire the Masquerade Bloodlines were both brilliantly designed levels, that were scare-fests, the latter still causes the hairs on the back of my neck to stand up whilst playing.
]]>I had a go on Siren once, the thing that freaked me out the most about that were the terrible controls! Frighting!
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