Aaron said:
do all the vampire games have to played at night?
No.
These aren't classic vampires. They can survive in sunlight, like normal people. Vampirism is just basically a prion disease, that alters the genetic structure of those infected. Though much like normal humans, the vampires do have some "classic" odd things about them: orange or red irises, fanglike teeth growing from the upper gums, and the necessity for blood. The prion disease causes a hemoglobin and protein defeciency, and so they must drink animal blood (not necessarilly human, though human blood is the most healthy for them) to get essential nutrients. An odd side-effect of the genetic modification caused by Vampirism is that, not only do they have hightened senses, they have a better control of their natural
ki abilities, the equivalent in this universe of a "soul" or "living energy" that one can channel through the limbs and eject it in the form of an offensive weapon. Of course, such a use of
ki are forbidden in sanctioned sports events and such, but they make excellent tricks in wartime.