He's (You're just assuming Shadow's male at this point) turned everyone against you and his next move is going to be hack them all for his own sick amusement. You're not going to let this fucker get away with this.

You go to your library and begin reading all the books on electronics and study your Shelter manual a lot. Soon you begin typing coding and making some harmless tests on your own computer. Given that you're starting to delve into the Shelter's inner workings, the Shelter begins to question what you are doing.

 
 
 
"Sir, what do you think you are doing? I've noticed you rooting around in my system; I'd rather you not do that. In fact altering or attempting to hack my systems in any way violates the GZS contract agreement; you should know that considering you've been reading the manual as much you have lately. Continue with this line of action and I guarantee you will not like my response."
"I'm not trying to destroy or alter your systems; I'm just doing some tests, before I launch my attack. I want to make sure my skills are up to this task."
"Sir, are you really serious about your concerns that this Shadow could hack other shelters? As you've been delving into mine, you can see I've been equipped with the latest protection technology. If you are really worried, you could just disconnect me from the network, your safety would be assured that way."
"No! I'm not going to let him beat me! I'm the only one who can stop him, the rest will see I'm right!"
"Sir, you're acting irrationally. You still don't have any proof and if you think I'm going to let you just hack Shadow's shelter think again. His shelter is also GZS property and as such falls under the contract agreement."
"Yeah, but the contract only says not to alter your own shelter, it doesn't say about others."
"Nice try sir, but hacking into another shelter would still fall under the anti-vandalism agreement of ANY GZS property, sub section 59 paragraph 3."

It would appear you aren't getting any further unless you can convince this automated lawyer otherwise.

You try to convince it that this is necessary

A little diplomacy is in order before you can do what you need to do.

"Surely you can't just let Shadow cause damage to his shelter and the other ones as well, and he'll be more successful as it would appear that those ones don't have a sophisticated AI to protect them like this one does. Think about it if you let me do what I have to do, only two shelters will have their systems messed with, and in your case it won't be even be detrimental, I'm just using your network system, but if you let Shadow continue with his evil plans, then not one, but ALL of the shelters are in danger. Would GZS really want to take the risk of losing five shelters? One of those being mine and aren't you supposed to want to protect me?"
"But…but there is no proof…"
"I'm asking you to trust me on this. I know humanity, and I'm telling you this Shadow character needs to be stopped. I felt the deviousness oozing from Shadow merely talking to him. Let me take him out."

The Shelter is silent for awhile and then gives you an answer

"Very well. I will allow you to proceed, but I will be monitoring you! And I also will be advising and guiding you to what I want you to do."

You log on and see that Shadow and most of the others are there. You don't talk to anyone you start immediately tracing Shadow's address. Rockerchick attempts to invite you, but you rebuff her, you got serious shit to do.

Soon you're in and you start rooting around Shadow's computer.

"This looks all normal sir, standard system layout for GZS shelters. Not as complex as mine but…"
"NO! I know he's got something hidden! I'm turning his power off completely, let's see how he likes going from dim lighting to none at all with no food or water!"

Suddenly a private window opens up on your computer, its Shadow! He's detected what you're doing!

Shadow21: What the hell are you doing you crazy motherfucker!? I knew you were psycho! It's a good thing I had the intuition to set up a warning system!
OmegaMan23: HAH! See Shelter? He HAS been altering his shit! Why would he do that if he wasn't planning something?
Shadow21: I did it to protect myself from your crazy ass! And I see you're still talking to the voices in your head. Well I'm putting an end to this right now; you're not the only one who can fuck with computers!

Shadow launches his attack and attempt to shut your power down, but now seeing that it is in danger your Shelter allows you free reign to do whatever as well as attempting to self fix anything that gets damaged in this dual of malicious coding. You sort of have the advantage because you have a more active AI to help you, but it's also a detriment when Shadow finds out a way to siphon power from you. Since your Shelter is more complex it requires more power to work properly and you're in danger of losing everything. You attempt to do the same thing to him to get it back, but it's a catch 22 you don't have the power now to breach his firewalls, you begin to panic and the only thing you can think of to correct it is to draw power from the OTHER shelters that are online.

The others seem blissfully unaware of this secret war you're having with Shadow and are guessing you two are working something out as it only appears to them that you're having a conversation in private.

You hack into MissKitty's shelter, out of the other four hers seems to have the most power, probably from all those luxury accessories she had the privilege of having. You don't think you just do it. This is war, there's going to be casualties and you're not going to be one of them. Soon your Shelter is able to break through and start wreaking havoc on Shadow's system. You drop in a virus and his files start becoming corrupted.

Miss Kitty's name disappears from the screen as does Shadow's. You think you have won. RockerChick tries to invite you again and you hastily accommodate her, while still analyzing your Shelter's diagnostics.

RockerChick20: What's going on? All of us are experiencing some power fluctuations here.  MissKitty just disappeared suddenly and so did Shadow, it didn't even say they logged off. What's going on? What were you and Shadow doing?
OmegaMan23: Nevermind! I'm trying to fix something here.
Job24: Welcome to my world.
CaseyJones22: Hey you know what's weird, one of my doors finally opened up. I think I'll…

CaseyJones' name suddenly disappears and Shadow's reappears in your private window again.

Shadow21: Well hey guess what? Casey's shelter had a lot of untapped power! You wanna play ruthless I'll fucking accommodate you dickhead!


Shadow sends a worm into your system which starts to slow it down. He's probably going to follow up with something worse while you're having problems. Your Shelter addresses you again for the first time during this battle, its speech sounds like it's in slow motion.

"Sssssssssir….nnnnnnneeeeeed….mmmmmmooooooore pooooooweeeeeer…."

There's only two candidates left, Job or Rocker Chick.

You hack Job

You figure you'll hack Job seeing as he's always having problems with his shelter anyway. At least you'll be able to be alone with Rocker Chick after all this is over. Surely she'll be grateful for saving her life from Shadow.

You start to siphon power from Job's shelter, but something begins to go terribly wrong! Job's shelter was faulty and barely worked properly to begin with, now you've just downloaded all the errors into your own! Couple that with the worm already in there, and your system becomes paralyzed and your computer locks up. You're at Shadow's mercy who follows up on your mistake very quickly.

The last thing you see on the screen is: "YOU LOSE ASSHOLE! LOL!" in great big letters.

Then it loses power.

Then your Shelter loses power.

Days later you lose power.