I filled in one weak point that has been bothering me for years. Why would anyone voluntarily become one of the undead? They are horrible creatures, and I don't care what Hollywood says. The whole effort to take shuffling zombies that drink blood to sustain their unnatural existence, and transform them into sparkly sex objects has always puzzled me.
There are undead in my universe, and I am a stickler for logical internal consistency. Or I try to be. I believe I have explained the ghaunts, finally. But the vampires were still nagging at me. I can see why victims become vampires, if the disease is communicable. But where did the first vampires come from? What caused it to come into existence, and why did it happen? Then it hit me.
Maybe the vampirism wasn't the objective? Maybe the vampirism was simply the price of doing business? I plugged it into the story and it actually fits. Hm.