Samus Aran:
How about zombies as enemies that can't be killed save by the few methods mentioned?
It's
sort of like an overriding aspect on the setting. Call it "Inexorable Foes" or something. When the characters are in a situation in which they lack the means to easily dispatch the foes, you're essentially invoking that aspect. Tell the players that they can't currently hope to kill the zombies without sacrificing someone, and give them each a fate point.
If they want, the players can use their skills and aspects to try to change or remove the aspect that's preventing them from killing the enemy. It's basically "Creating an advantage." You would set the difficulty (figuring out how to kill zombies in an open field would be harder than figuring out how to kill them in a hardware store) and they would make a check to see if they could create a helpful aspect. Or, maybe they just give their fate points back and say "Look, we're in a Costco and we each have a feat that makes us good in combat and in improvising weapons. We can kill zombies."
It's all about aspects.
Samus Aran:
Also, how would you put some rules to something like "Loud noises and things you make can draw zombie attention"? That's one of the things I considered for a possible like environmental stress track or the like. Breaking windows, shooting guns, yelling, etc., all has a potential to draw zombie attention and maybe bring down a horde on top of you.
None of those things need extra rules in Fate. They can all be handled by aspects, skills and challenges.
As a challenge:
https://fate-srd.com/fate-core/challenges
They're sneaking around downtown to find parts for a radio. They need to find the store (Notice), get inside quietly (Burglary), and lug the equipment out (Athletics). Maybe toss in a general roll for being quiet (Stealth).
You come up with the difficulties, and then the scene is narrated, with spots in the scenario for those skills to matter. As the rules say "after the rolls have been made, you’ll consider the successes, failures, and costs of each action as you interpret how the scene proceeds. It could be that the results lead you into another challenge, a contest, or even a conflict." Or, maybe something happens as soon as they flub a roll. Maybe they can succeed with bad rolls, but only at a cost, like someone hurting their back keeping a rusty shelf from falling (earning them an aspect like "Serious back injury," which is bound to earn them lots of trouble and fate points in a zombie survival setting).
As simple as they are, I think challenges can be the core of most Fate games. Combat doesn't impress me much, and contests don't seem like common occurrences. It's worth noting that the example in the book is of someone holding off zombies, and that even Fight is mentioned as a skill that can be used in a challenge.
While everything has aspects, arguably they're not all on the table at once. We don't need to list that a machine gun has "Makes a huge racket," "Burns through ammo," and "Wildly inaccurate," even though those are all true and valid. I don't know if this is entirely supported by the rules, but I think it's proper for you to invoke aspects like that. If they're facing one zombie and all they have is Grandpa Vito's old Tommy gun, then tell the shooter "The gun makes a tremendous noise that can be heard blocks away," and hand them a fate point. This is the basic transaction for when something about someone (or about something they have or are doing) is going to cause them a problem. It's the inverse of "something about someone is going to help them out, so they hand in a fate point."
Make sense? I recommend wringing everything you can out of the basic rules before you start layering other stuff on. Otherwise, I recommend using a different system and taking useful advise from Fate, of which there is plenty.
This message was last edited by the user at 14:33, Thu 17 Aug 2017.