It is difficult to state when vampires first came into being. There are many different tales, some more reliable than others. The modern day term "vampire" most likely derived from Slavic origins. The Serbian word "vampir" was incorporated into the German language, then to the French as "vampyre" and finally into the English "vampire." These undead horrors have various abilities and powers depending on folklore and place of origin; literature and cinema have also had a lot of influence on the vampire image. According to Eastern European folklore, the dead become vampires because demons or evil spirits enter the bodies. Vampires are also said to be dead werewolves, witches, criminals, suicides, and heretics: persons whose beliefs are contrary to the church doctrine. Again, sources vary, but a victim of the vampire's bite typically rises again as a vampire after death.
Vampires often possess higher physical strength, dexterity and sharper senses than their mortal prey. Some may have the ability to take the form of a bat, wolf, rat or mist/smoke. The vampire can influence some animals - typically wolves, bats, and rats. They can scale vertical surfaces and can use an uncanny hold on a victim through their mesmeric gaze. If a vampire has a masterly hold on a human victim, it may be using said victim over a period of time as a constant source of nourishment.
Weaknesses include silver and sometimes iron which will cause the vampire pain. Similarly, in some traditions, the wood of the hawthorn tree, which has Biblical roots, will also harm a vampire. Holy religious symbols can be used to hold the creatures at bay. Vampires also seem intolerant to garlic. Vampires, being nocturnal beasts, cannot function in sunlight; indeed, exposure is fatal in most folklore and adaptations. Some vampires cannot cross running water, and most can only enter a property if personally invited inside.
Burying a victim face down or placing poppy seeds in the grave of the deceased will, according to legend, prevent the resulting vampire from rising. Others can be tracked down to its lair, generally, the place they where buried - a tomb, grave, mausoleum, or even family estate - they can be disposed of traditionally with a wooden stake through the heart. Severing the head will assure destruction.
No one knows where vampires originate, possibly even the vampires themselves. They go back to before the Roman empire; but generally, it is believed that it was the Roman empire's expanse is when the first society of such beings were able to come together and create some sort of formal guidelines and attempt to unite.
Vampires are not living, not be the technical definition and therefore can be considered a subset of the Undead. Without the need for regular food, water, or even air they maintain this facsimile of life through an instinctual unholy thirst for blood. Human blood is the preferred source, but animal blood can suffice and the blood of some supernatural creatures can be a dangerous delicacy for elder vampires while other beings possess blood that is the equivalent of poison to a vampire.
In addition to other effects, a vampire's own blood carries the preternatural enzymes which convert a human corpse into a vampire. The process for creating a new vampire usually requires a seasoned vampire whose palate has evolved enough to detect the metaphysical qualities of their victim's blood to test for susceptibility to the vampire conversion. The process also requires a near-corpse, a human with the right metaphysical markers whose blood has been drained to the point right before death. The vampire predator then drips some of their own blood into the victim's mouth at the right moment. Too early and the victim becomes a thrall bound to the vampire (provided they don't die from blood loss), too late and the change does not have time to take effect and the victim becomes nothing more than a corpse (or in certain cases a revenant or ghoul). If the timing is right, the human undergoes a fit comparable to seizure. Some newly risen vampires are left to break from this fit and slip into a different fit, a feeding frenzy where they immediately go on the hunt for fresh blood and gorge themselves; but most careful predators use their abilities to sedate their offspring before the feeding frenzy has begun and instead hide them in a grave or in a chamber in their lair, where they keep them contained as they go out and over time bring them the blood they so desire, slowly quenching their new thirst and then only awakening them from this torpor when their mind is once more clear and ready to receive instruction.
A vampire's senses are enhanced far beyond those of a normal human being. While the degrees to which this may vary between vampires there are a few constants. Most vampires have exceptional hearing and smell, particularly tuned to the sounds of beating hearts, pumping blood, and the smell of open wounds or spilled blood. Most are also possessed of exceptional nightvision. Some also have a remarkable sense of touch, particularly able to feel vibrations in the earth to know the locations of nearby movement. A few vampires have been known capable of gifts like aura reading and thermal vision, but these are the exceptions to the rule.
So long as vampires continue to consume blood, they will not age beyond the physical state they were in when they first became a vampire. A vampire deprived of blood for a long period will continue to age, even to the point that they look like nothing more than a dried and withered old corpse but after drinking their fill, their appearance and vigor will return to them. A vampire cannot be killed through lack of blood, only driven insane and weakened tot he point of immobility.
Vampires are invulnerable to most forms of injury (certain exceptions apply). Bullets, blades and blunt objects do little to no damage to a vampire's body.
In addition to being virtually indestructible, whatever damage a vampire does in fact suffer can be healed through the consumption of human blood at a remarkable rate.
A vampire's strength level is several times that of a normal human being and they are considered superhuman. While the precise level of strength varies from vampire to vampire, all vampires are much stronger than they were in mortal life. The weakest vampire can easily match the lifting power of an Olympic athlete and the average vampire who has recently fed has strength equal to Class II strength. A vampire who has gorged itself on blood may be even stronger and there are some vampire bloodlines that have a refined gift for exceptional strength matching Class VI or greater levels of strength when fully powered.
So long as they continue to consume blood, a vampire can function tirelessly without rest or relaxation.
Not all vampires are psychic but most have some degree of psychic ability. Whether this is psychokinesis, hypnotic stares, mind control, telepathy, or all of the above--or even other more exotic powers. Almsot all vampires have exceptional psionic potential and they can learn new disciplines rather quickly provided they have a knack for the esoteric study or a willing mentor.
Again, not an ability shared by all vampires, but common enough. Many vampires often possess the ability to transform into a variety of creatures or effects such as bats, wolves, rats or even mist. While their physical attributes may fluctuate during such states, a vampire's mental acuity is the same as that when they are in their human shape. A vampire who transforms into an animal may also benefit from that particular animal's attributes (often heightened to a preternatural degree) including razor-sharp claws, fangs or the ability to fly.
Similar to the transformative ability above, some vampires often demonstrate the ability to not only mimic the shapes of other creatures but to freeform alter their appearance at will to acquire things such as claws, elongated fangs, wings, or assume the look of a specific person. While some of these are considered to be advanced techniques, nearly all vampires can master the development of claws and sharpen their fangs after their first few feedings.
Some vampires, particularly the elder vampires, might even practice the dark arts and be skilled warlocks or sorcerers. Among their own kind, these vampires are known as a 'lich'. They are probably best left to only the most skilled monster hunters.
Some vampires choose to surround themselves with minions, persons who the vampire has chosen to give a fraction of the vampiric power by regularly letting these humans taste the vampire's blood, endowing them with superhuman strength and resilience, but at the cost of their own free will. They become slaves not only to the vampire whose blood they have tasted, but also the taste of the blood itself. They can experience painful even fatal withdrawals if deprived of this craved sustenance. While the exact length of time this mental servitude varies depending on the quantity and quality of their vampiric master's blood, the typical feeding can last an average thrall a solid week; while elder vampires can keep loyal thralls for months between feedings.
As mentioned above, vampires can have different variations on their powers and abilities. Every vampire is truly unique and even among those vampires who choose to hunt in packs, one member of the pack might exhibit radically different abilities from its packmates. Partnered vampires, particularly those with a mentor and pupil relationship may share many of the same abilities, many hunters mistake the pupil for the mentor and vice versa which can be a truly fatal error, but one easy to mistake as a vampire's appearance can often be deceptive of their true power.
Despite what Hollywood would have you believe, sunlight does not turn vampires into ash. No. Nearly all vampires are extremely sensitive to sunlight or even bright light. While most seasoned vampires learn to tolerate it, very few find such things to be pleasant in the slightest. Not only does this give vampires discomfort, but while exposed to such light, vampires usually find it more difficult to concentrate and therefore have difficulty using their esoteric abilities or sometimes find it hard to even act human. Often these sorts will hiss and scatter like a wild beast rather than anything resembling sentient when confronted with an unexpected cascade of natural light.
The only truth to this old wives' tale is that garlic can be an ingredient in a variety of alchemical potions and concoctions which can affect vampires in a variety of ways. Raw garlic has no effect on the undead, except for possibly agitating or overpowering their sensitive noses.
Driving a wooden stake through their hearts does not kill a vampire, but impaling their heart with anything substantial (wood, metal, plastic, an arrow, et cetera) will prevent their undead heart from healing and until it is healed, the vampire's abilities and even their basic mobility will be greatly impaired. Only the most willful and driven vampires have been known to be able to extract something from their own heart when impaled in this manner.
These trinkets are just that, mere trinkets, usually... A person with an exceptional sense of faith (sometimes defined as a 'Belief in a Better Reality') who brandishes such an object in defiance of the unholy mockery of life before it, with the actual intent to deny the monster will find themselves protected by a preternatural force which exhibits a degree of influence on reality, preventing the vampire the ability to advance any closer than they already stand.
Vampires must constantly drink the blood of the living in order to remain not just youthful looking, but also ageless. If they do not feed on blood for a prolonged period, vampires start to diminish and eventually succumb to a deep sleep after which only the taste of blood can awaken them (sometimes just the smell of nearby blood is enough to cause them to stir enough to attempt a hunt).
There are a few techniques to suss out a vampire. Literature would tell you vampires do not possess a reflection. While this has some truth, the original folklore is that silver would not reflect a vampire and since the fluid used to develop film contained silver and mirrors themselves were actually just polished silver, the lore became simplified in that vampires cannot be photographed and have no reflection. Silver is rarely used in modern mirrors and photography so unless a digital camera has silver wiring or a Liquid Silver Display screen, then the vampire should not show up in digital media. For this reason, and to use against werewolves, many seasoned monster hunters will keep a silver blade of some sort which is kept to a high polish to allow a good reflection to be seen in order to make certain their target is a vampire before they impale them.
Usually associated with harming werewolves, silver is actually an exceptionally useful material against many forms of supernatural predators. Though a silver bullet is not especially effective against vampires any more than a normal bullet; wounds caused by silver heal at a much slower rate. The touch of silver will also have the similar effect as daylight on a vampire, often causing them to reel away if they touch something they did not expect to be silver. With practice and focus, a vampire can overcome this inclination and handle silver, but doing so is exhausting and prolonged periods of such will test their will and sap their blood reserves, stirring their hunger. Silver chains or handcuffs could be used to capture a vampire, but doing so for prolonged periods could drive them to a hunger madness and a hungry vampire is often the most dangerous kind.
Magic: While magic themselves, vampires are susceptible to many magical effects. As a supernatural being, a summoner could summon a vampire provided they know the proper rituals and incantations, and know the vampire's true name. Likewise, a diabolist or occultist skilled in warding can fashion circles or runic inscriptions specifically devised to torment, enslave, capture, bind, or harm a vampire whether as a vampire specifically or as a member of the undead generally.
Focus: Vampires are dead. They are cold, lifeless corpses animated through what basically amounts to blood magic. They do not breathe. Their touch is cold and chilling, filled with dread. In order to sustain the illusion of the living, a requirement when masquerading as a human, especially in public spaces or when up-close and personal with their prey, a vampire needs to remember to breathe, will their heart to pump blood to fill their veins and tissues with warmth, and resist the urge to vomit up foods and drinks which their stomachs no longer can properly digest. To combat this, most vampires develop a technique that acts as a sort of 'subroutine' in their brain, that more or less 'automates' this deceptive process when the vampire chooses to activate this facade. While this technique does burn through the vampire's reserves, most find it a necessity for survival and are willing to pay this price.
Lair: That said, few vampires are willing to keep this effect up when alone or in the company of other vampires. This need to relax the taxing illusion has led to clever vampire hunters sneaking into a vampire's lair and awaiting their return. While the hunter is concealed in a location with a good vantage point, they observe the vampire, waiting for them to drop this disguise. Many vampires have succumbed to this tactic time and time again, but then again so have many hunters as hiding among the vampire's lair is truly a dangerous gamble.
Vice: This weakness can also be exploited as a vampire's focus is needed to utilize its advanced gifts and techniques. While immortality often gives vampires the time to learn patience and develop their willpower, it also has cursed many vampires with the need for distractions to fill the time in their long lives and pass the time. Whether it is the offer of wealth, sex, adventure, or fine food (whether gourmet food or the refined taste for a particular type of blood) - every vampire has a vice to exploit and many have multiple.
The only practical way to 'kill' a vampire is to sever its head from its heart and burn both the brain and the heart in two separate pyres and scatter the ashes in different areas, preferably miles apart. If time is scarce, many prefer to simply behead the vampire and take the head; while other hunters torch the body and toss the head aside. But these methods are all somewhat flawed. If too much of the scattered ashes mingle and are exposed to blood, the vampire will begin to reform. Vampires from centuries past have awoken on or near battlefields thousands of miles from their last known location, having been reborn among their own ashes and spilled blood like an unholy phoenix. This is a particularly grisly sight to see as the partially formed vampire will be little more than sinews, bones, and unformed flesh until it feeds on enough blood. Some may carry this tainted look or remnants of it for months or years after such a nasty resurrection.
If a vampire could be atomized, it should, in theory, cease to exist. However, that's a technique which most vampire hunters are not usually capable of pulling off.