Sarah Behan. 20. Computer science junior at a state university in Illinois. I bought System Shock 2 the week it came out in August, at the mall back home, with money that was supposed to be for books. I have now finished it twice, once as a Marine and once as an OSA psi user, and I have a data structures exam in two weeks that I am going to be fine on. Probably.

My roommate Dena says she can tell what deck I'm on by the noises I make. She says Hydroponics is the worst. She's right.

And yes, before anyone e-mails: I'm a girl, I play games, I'm sure.

System Shock 2 is a first-person game from Irrational Games and Looking Glass. You're a soldier with a cybernetic implant who wakes up on a starship, the Von Braun, on its first faster-than-light trip, and something has gone horribly wrong with the crew while you were out. You find out what by listening to the crew's audio logs, which are scattered everywhere, and by what's walking around the corridors.

It looks like a shooter, but it plays more like a role-playing game. You build your character. You have stats and skills and an inventory that's never big enough. Ammunition is scarce. There's no way to be good at everything, so every choice costs you something else. It's also the scariest game I have ever played, and I watched The Blair Witch Project in a theater this summer.

You build your character at the start by enlisting. First you choose a branch:

• Marines. Bonuses to weapons. You can shoot. This is the easiest way to play the first time, and I recommend it.
• Navy. Bonuses to the technical side, especially hacking and repair. Fewer guns, more problems solved with your hands.
• OSA. The Office of Strategic Analysis. You start with psionic powers and the psi amp you need to use them. Powerful later, fragile early. My second playthrough.

Then you serve three tours of duty, one a year, and for each one you pick an assignment from a short list. Each assignment gives you a bump in different stats or skills. So two Marines can come out pretty different. Read what each one gives you before you click. I didn't, the first time, and ended up with a Marine who was very good at something I never used.

Stats (the five numbers that are you):

Tech skills (the five things you do with your hands):

There are weapon skills too (Standard, Energy, Heavy and Exotic), and psi has its own set of disciplines in five tiers.

Cyber modules are what you level up with. You get them for finishing objectives and you find more lying around. You spend them at upgrade units around the ship: stats at one kind, tech skills at another, weapon skills at another, psi at the psi units. Every level of anything costs more than the level before. So you will never, ever have enough. My rules:

1. Pick a lane. Decide early what you're going to be: a gun person, a tech person or a psi person. A little of everything means you're bad at all of it by the time things get hard.
2. Buy what opens doors first. Literally. Enough Hack to get into crates and past keypads pays for itself in ammo and modules.
3. Get Maintenance if you use guns. Not optional. Read the next entry.
4. Endurance is never wasted. More hit points is more mistakes you're allowed.
5. Don't spend everything the minute you get it. Sometimes the next deck shows you what you actually needed.

The wrench is the first weapon you get and you'll be swinging it for longer than you want to. It's a wrench. It doesn't need ammo and it never wears out. When you're out of bullets, and you will be, it's what you've got. Learn to time your swings and back up between them.

Guns are different. Every gun you pick up has a condition, and every shot wears it down a little. When the condition gets low the gun starts to jam and act up, and eventually it breaks outright. A broken gun is a paperweight until you repair it, which takes the Repair skill. So:

• Pick up every maintenance tool you see. Use them on the guns you actually use, before they get bad.
• Put some modules into Maintenance so each tool does more.
• Carry a spare of your main gun if you have the room.
• Use the right ammo. Armor-piercing for robots, anti-personnel for anything made of meat. You'll use fewer shots, and every shot costs you condition.

People on the newsgroup complain about this a lot. I get it. But it's part of why the game is so tense: you can never just hold down the trigger and feel safe.

There are monkeys on the Von Braun. Lab monkeys. Something got to them too, and now they throw psionic blasts at you from across the room, and they screech, and they are small and quick and very hard to hit with anything. They show up in the middle of everything else and you can hear them before you see them.

I have died to monkeys more than to anything else in this game. More than to the things that are supposed to be scary. Monkeys. Shotgun if you're a Marine. Cold blast if you're psi. Wrench if you're desperate, and good luck.

Dena now makes the monkey noise at me when I come home from class. I'm going to move out.

1. Find the Quantum Bio-Reconstruction machine on every deck and turn it on. Once it's activated, if you die on that deck, you get rebuilt there for some nanites instead of going back to your last save. It has saved me dozens of times.
2. Listen to every audio log. Door codes are in them. So is the whole story.
3. Hack the replicators. A hacked replicator drops its prices. Nanites are tight.
4. Security cameras set off alarms, and alarms bring company. Shoot the cameras or hack a security computer to switch them off for a while.
5. Save a lot. In more than one slot.