I decided the idea of cannibal vampire types in Fallout was pretty groovy but I think I want to go one step further than the game does and give them a mutation in which they are in fact actual vampires of a sort and not just creepy flesh eating weirdos. The Forced Evolutionary Virus opens all kinds of doors for odd, semi plausible mutations and with vampires this is what I'm thinking. Vampires, start out as regular people who have been exposed to the F.E.V but like ghouls, for whatever reason their DNA causes a specific mutation (vampirism or what have you) and they eventually become 'vampires'. Their bodies can't make a particular protein or type of cell or whatever on their own anymore so they have to get it from people. I think the idea of them kidnapping people or buying slaves then keeping them alive and doing creepy blood transfusions on themselves is way more interesting that just drinking blood. Maybe some of the ones that are off their rocker do drink blood or eat flesh, but I think that's sort of old hat zombie type stuff everyone is familiar with already. So in addition to that, they will be more resistant to radiation and disease and will heal quicker than a non mutated human. But they will be highly allergic to sunlight, but not because of the light. I had the idea that there is something produced by their cells when exposed to natural light (kind of like the vitamin D thing in normal people), which causes a serious allergic reaction (non beneficial mutation!). They still have to eat, sleep and breathe, etc. And they may be horrible disease carriers considering their direct exposure to blood born pathogens.
I did have this idea of a merc company of vampires wandering the wastes, swathed head to toe making them look creepy and mysterious, called the Midnight Runners. Yes, after the pop group. Maybe their leader found an old poster or cd...
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