Ok, so here's the story.
The year is 2013. For the past year, the zombie apocalypse has been raging on. The population of humans were quickly decimated by the zombies in less than six months. Only pockets of survivors exist. No one is safe. In the thread, every one knows who caused the virus. In 2012, a group of scientists where researching on the effects of a mixture of plutonium and magnesium. They attempted to heat it, which caused a blast that infected all of the scientists. Within 24 hours, they died, and came back. They got out, and began to spread the virus, causing havoc. The CDC learned that the undead did not completely rot, and they werent affected by the enviroment like dead bodies should be. No cure was ever found.
There is no super weapon that anyone has that will keep them permanently safe. No one is immune to the virus. Everyone does have limited amounts of ammunition.