I've only played this for maybe an hour total and it is already scarier than anything I've played before. This includes FEAR, Dead Space, Bioshock, and Resident Evil 4. I'm not much for scary games in general, and as such I find it difficult to play SS2 continuously. I try, though, because it is undeniably a quality game. Here's why:
The gameplay is much like Bioshock. You explore a sort of living envinronment - a nonlinear world with unscripted enemy AI that will attack you on sight. There are weapons - with very limited ammo, of course - as well as "psionic powers", much like Plasmids in Bioshock. These can freeze enemies, move objects telekinetically, or light things on fire. Beyond Bioshock, however, is an extensive RPG-style stat system and inventory. Everything in the game must be dealt with in real-time. Nothing in-game will pause it, including inventory screens, computer interfaces, or stat upgrades. Of course there is an escape menu that lets you save, load, change options or quit, and this does pause the game. A totally real-time gameplay experience is a feature that many people consider Dead Space as famous for developing, but clearly SS2 came first, which surprised me. (On a side note, many people also consider Dead Space innovating the concept of a HUD built into the character's player model. This is also not true, because Roboblitz did it first. Interestingly, Roboblitz is a great game that was the very first to make use of the Unreal Engine 3, something people falsely credit Bioshock with.)
This always-real-time experience is part of what makes System Shock 2 such a scary game. If you want to stop and read a computer screen or a text log, you need to be careful because a mutant could attack you while you do so. If you want to shuffle your inventory around or use some items, you need to keep an eye out for enemies. It's very tense, made even more so by the fact that enemies WILL appear right behind you. The first time I encountered an enemy in the game was most astonishing. I was wandering through a corridor, and saw an item on the ground. I looked down at it to pick it up. When I looked back up and turned around, a mutant was an inch in front of me in the middle of swinging a wrench. I jumped out of my seat, my hands momentarily left the keyboard, and I took damage. When I regained my wits I bludgeoned him with my wrench, pleasantly finding that they only took a couple swings to kill. Every time I met an enemy, I experienced that same feeling of surprise and fear, because enemies appear infrequently and often startle you. As soon as they spot you, they will run straight at you and try to kill you, so any time you spot one of these mutants you have to immediately deal with it. This is different from Bioshock, where splicers will often ignore you if you're not very close.
That's all I'm going to say on this game, because I can't stand to play it too long on account of how I don't particularly like feeling startled a lot. I enjoyed playing Bioshock more, but I understand the reason many people prefer SS2, and even consider it one of the greatest games of all time. It's very high-quality, even if it doesn't appeal to me personally a lot.
Next up, Mirror's Edge!
