Several RPs I play have monsters as playable characters in the thread, but I have different interpretations of some of them that differ from what's in popular media.
A vampire is essentially a dead person, whose body is reanimated after they die and must feed on blood to continue existing among the living. However, though the stories of vampire lore do hold some truth many of them also contain many lies. The vampires of today are probably more dangerous than the stories you're used to, but they are also smart enough to conceal what they do in such a way that it's as if they were never there. Only those with ties to the supernatural are enlightened to their existence.
Currently, there is only one known way to make a vampire. A vampire must choose a victim, drain them nearly out of their blood, and then have them feed from their own until their victim succumbs to the transformation. The transformation does cause a few notable changes in their bodies. As vampires do not need to breathe to continue living their skin does pale from the lack of the circulation of blood, but some do continue just so they can better hide among the living. A vampire's most notable feature is their eyes, which are black and tend to be hypnotic, putting those that get caught in their gaze in a trance. Vampires usually change their eye color with their powers, yet the trancelike state their gaze produces remains.
The strength of a vampire is determined by a few factors. Though age is taken into account - an old vampire is naturally stronger than a young one - the willpower an individual had before being turned can also influence their strength. As a reward for fighting the transformation, their strength grows at a rapid rate. This willpower can manifest itself physically, by harming their sire in some shape or form, or by fighting to hold on to their humanity rather than succumb to it. If someone is turned willingly they are considered weak and are fated to not grow that much stronger even if they do turn out to live for a long time.
One of the most common lies in vampire lore is their weakness to sunlight. Vampires do not burn in the sun, or even sparkle, though the sun does hold a sort of power over them. All the talents a vampire possesses aren't available to them under sunlight leaving them almost as defenseless as humans. However, once it's dusk and their powers begin to emerge, it's easier for a vampire to hunt and then they are far from defenseless. Aside from the sun, crucifixes and silver do not harm them as well, though it's rare to find a vampire who finds solace in religion.
The bite from a vampire can do many things. Most of the time a vampire will put someone to sleep, but if a vampire chooses to keep their victim awake the bite can cause an immeasurable amount of pain or a great deal of pleasure - usually the vampire's choice. While drinking a victim's blood a vampire can learn virtually everything about them, including everything they've ever seen or experienced. Fledgling vampires usually can't stop themselves from draining a victim completely, but as they grow older and stronger it becomes easier to control their blood lust.
Vampires possess heightened senses and supernatural strength. The sense of scent of a vampire is 20 times stronger than the average bloodhound and they can hear whispered conversation over great distances, so it's hard to keep anything hidden from them. They also heal very fast - cuts and bruises heal in seconds, and it only takes a few minutes of rest to recover from an injury that would disable a human permanently. However, it is possible to scar a vampire with weapons tinted with magic or with weapons laced in vampire hunter's poison or vervain, which is fatal to a vampire if consumed in large quantities.
Despite a vampire's physical strength, it is unusual for them to use it while fighting one another. One of the first abilities a vampire gains after his or her transformation is the awareness of that part of the brain that's unavailable to humans while they're alive. With this part of the brain unlocked a vampire has the power to do things such as manipulate minds, shapeshift, and read the auras of other creatures, determining their species and strength. Within time, a vampire can cloak their aura, send out psychic blasts to fight with, and if a vampire is exceptionally strong, summon elements. A surefire way for a vampire to become stronger though is for them to feed than another. Vampires can't be drained from their blood, but if another vampire feeds from them any way to block out the other vampire from their mind disappears.
A unique skill available to vampires is the power to transform into ether, or pure energy, and transport themselves to another place almost instantaneously. Using this skill, however, tends to weaken a vampire temporarily and keep them defenseless. Also, the farther a vampire travels in this form the longer they'll be weakened, so even though it is an interesting little gimmick, you'll rarely find a vampire in this form.
Another myth from vampire lore is that vampires sleep in coffins. Vampires might rise from coffins but they are in no way connected to them. A myth that happens to be true though is their lack of a reflection. Fledging vampires do bear a reflection, but as they grow older their reflection begins to grow faint, and older vampires have no reflection at all. Also, most vampires tend to be drop-dead gorgeous as the transformation tends to clear out most impurities.
Even though vampires tend to be independent they do have a ruler named Luciano, who was the first vampire in existence and therefore one of the strongest in the world. Luciano does not answer where vampires came from and even though he does rule over vampires, is rarely seen. Luciano formed a vampire community known as Aramore which is the only real unified community of vampires in the world. Aramore's location is secret and most vampires receive the location by invitation only. Humans who find the community are simply killed or turned (usually the former) so the location won't be compromised.