Spontaneous Combustion

A werewolf doesn't transform into existence, it is exchanged into this world from a parallel universe. That transportation is painful and violent because the world it comes from is dominated by evil magic. After a bizarre experience with a UFO, Greg finds himself spontaneously combusting. Then, everything turns upside down. He finds himself involved with a group of people that have also spontaneously transformed. Greg combusted, so he is now made of fire. Others are made of air, water, lightning, and shadows. They only have two things in common. They all had a weird experience and they are no longer at the top of the food chain. They are now the main course for the werewolves. Outside of the real world, but able to see it, Greg finds that the only way to survive and try to get back is to use magic. It is readily available, but he can't access the good magic. He has to use the evil, and it exacts a terrible price.