For no money down, there is a great time to be had here.
I'll admit, I never played the first one, but after watching the introduction I could tell it hardly mattered. The events of the first game were summed up in the first two lines and after a brief overview of the game I was about to play, I was all set to go.
In System Shock 2, you are a soldier who was apparently recruited at the last minute to serve as security on board the Von Braun, the first starship capable of faster than light-speed travel. After a somewhat confusing sequence detailing some emergency surgery, you emerge from a cyrogenic sleep to discover that something on the ship has gone horribly wrong. Armed with nothing more than a wrench you find lying around, you soon begin to encounter humans infected with some sort of parasite. As you try to get power restored to the elevators without the main computer knowing it, the happenings aboard the ship begin to reveal themselves through the audio logs of the terrified and now most likely dead staff, and you slowly begin to realize the true magnitude of what you're up against.
The graphics of System Shock 2 are pretty mediocre. The environment is pretty cool, but occasionally dull since you never actually leave the ship. The character models, however, are rather lousy. The hybrids you face are blocky and bland, while the humans you find suffer from what I call "triangle feet." There is some good news, however. A mod was made that greatly improves all the worst character models, so although they don't really move more or change their facial expressions, they do look much cleaner and even a bit scary.
The sounds, on the other hand, were dead-on. There was a wide array of voice-acting for all the audio logs, some coming out kind of bland, others, dare I say, frightening. The weapons are great, and make different noises depending on the surface they hit. In addition, nearly every enemy you face will try to talk to you. Some hybrids moan about the joy of The Many, while others will try to warn you, and beg for death when injured. On the other hand, C-3PO-like protocol droids will continue their charade of helpfulness – "Sir! I believe I found what you're looking for... where did you go?" – right up until they get close enough to take you out in a suicidal explosion.
Throughout the game, you find a VERY wide array of weapons, reaching from your ` key out to the equal sign, and you can load several weapons with different types of ammo, for armor piercing or other purposes. Most weapons also come with an alternate fire, and leaning is even allowed.
It's not all a shooter, though. In many RPGs, I find that the game is hard at the very beginning until you can get a few level-ups, then it becomes super easy for a while, then you get to a certain badass boss and have to go back and level up a few more times. Other times, it just becomes easy throughout the entire game. That didn't happen here. This shooter has a level-up process, which works not by killing opponents, but by using cyber-modules, which can be found by exploring and are also awarded to you for completing objectives. On easy, you could probably get away with just wrenching everyone to death, but on the harder difficulties, you will need to upgrade your stats and skills, which consist of weapons proficiency, hacking, repairing, and a few others, as well as a well-devloped "psy" stat, which allows you to perform all kinds of both useful and incredibly pointless abilities. I'm not so sure anything in this psy list is worth the points you have to spend on them to get anything good, though.
One bizzare thing about this "RPG" is that there are tons of items, but nothing resembling a shop at all. You can get a "recycler" later, that can turn small, useless junk into money, but for the most part a useless item is a useless item. In this game you must learn that when you find something you don't need, you'll actually have to let it go. You can only carry so much, and there is a LOT of unhelpful junk. An interesting note is that you hardly even "meet" anyone throughout the game. You mostly communicate through diary entries and the stream of e-mails from one or two supposedly omniscient guides.
Playing through the game, I don't think I received the effect the game went for. Had the graphics been better (I didn't know about the mod when I played through it the first time) and the music more immersive, I might have been scared by this game. It was a highly innovative concept and Shodan was simply an awesome character. Lack of polish notwithstanding, I loved it.
Highs: Immersive experience, great story, characters that manage to be kickass without ever even getting to introduce themselves, combat that lets you dodge. Oh, and it's now free. Did I forget to mention that?
Lows: A bit too much running around, bland graphics, that nagging feeling that you won't find another healing station for a while and you wonder if you should turn around, being a psy-user sucks.
Bottom Line: Anyone that likes a good ghost story or an offbeat RPG should find a good time in this game. Hardcore FPSers, "You'rrrre not wwelcome heeeeuuurrr."