An artificial and accidental creation of Rubiceye's assistant Gloam'Eye during their efforts to develop Necromancy. Vampires first came into existence shortly before or around the begining of the Mage Wars; the exact date is unknown, but by B.G.A. 3500 they were fairly common.
Vampires do drink blood, but rely on life force to sustain them. This is best extracted through very fresh blood, and is purest in humans. Some vampires have been known to feed on animals, but this does not sustain them as long as human blood.
Armies of vampires wrought havoc durring the Mage Wars, where conflicting theories about how they could be killed made fighting them very difficult. Various traditions held that fire, beheading, or a wooden stake through the heart were required to end a vampire.
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No special 'recipe' is required to kill a vampire. While they have a near limitless ability to self-heal, at its core a vampire is just an organic machine. It has working parts, and if enough of these are damaged, the machine will break. Explosives are probably the most straightforward technique, though vampires are much more durable to grenades that most humans.
Part of the myth of vampires as unkillable comes from the fact that they do not feel pain, nor suffer from shock. A bullet to the chest, for example, may kill a vampire if a major artery is severed, but it won't kill them any faster than it will a human; and while shock and pain might make a human fall, the vampire will keep attacking.
The challenge lies in dealing enough damage fast enough. While a bullet to the spine will sever the cord, it will heal almost before the vampire has a chance to fall down. This is where the myth of severing the head came from, and in truth separating a vampire's head from its body is among the most effective ways to kill it.
Death by bloodloss is ultimately the most effective improve-strategy. Vampires do need blood (their own blood) to operate their bodies, so severing a major blood vessel will get the job done. This is most effective if it is a high-pressure artery where the blood can escape too fast for the vampire's self-healing abilities to close it.
Vampires do not "burst into flames" in sunlight as common myth holds. However, their bodies are very weak and vulnerable to the raw form of magical energy coming from a star, and thus sunlight will cause severe burns in a short period of time. Because of a vampire's self-healing abilities, these burns will be mostly cosmetic. The real advantage to luring a vampire into sunlight comes from its highly sun-sensative eyes: vampires can barely see see in direct sunlight. Be wary of vampires sporting shades.