So today, I was thinking about the third episode of Red Hood Rider a bit, meaning I built up the lore of vampires a lot again. For starters, I've invented something they use in combat: the Impaler Stance, the foundation of the vampiric martial art used by the Darkblood, Dragul, and Zu clans, especially their elite members. (Ruby, being the current lord of the Darkblood coven, has received training in the style, albeit just the basics at the beginning of the story. She mostly uses Herald's style of martial arts instead.)
It's pretty similar to a standard fighting stance, with a little more weight on the back foot (so, like a hybrid between a fighting stance and a cat stance), with the back hand being straight in a 'knife' formation, and the front hand being clenched in a fist to act as a 'shield', because the stance is equal parts hard and soft, offense and defense, useful against humans and vampires alike, and is very hard to counter in 1-on-1 fights. (It is, however, very easily countered if facing multiple opponents, so mainly gets used when dueling a single foe.)
It works by taking advantage of vampire biology, enhancing their strengths. They have clawed fingers, which cannot be shattered, bent, or broken in any way, and because they're vampires, their fingers are unlikely to bend or have bones break, too. (Not impossible; vampires can have bones break and joints involuntarily bend according to momentum, it's just really hard for that to happen, to the point where no human, not even armored, can cause it.)
In short, their claws act as a five-pointed trident/spear of sorts, able to puncture through any incoming attack. This works as both an offensive attack (where they wind up their shoulders, twist back, and thrust forward with everything they have), and as a defensive counterattack (where they use their shield hand to grab an opponent/opponent's weapon, then do a smaller, weaker, but still deadly thrust forward while their foe is incapacitated), basically allowing for a one-hit kill no matter the circumstance.
Their shield hand can protect from most weaponry, taking advantage of vampiric toughness: the average vampire is tough enough that, say, a sword swing will not lop their arm off. Maybe the sword could get down to the bone: maybe. (Tougher vampires will have it not even break the skin!) But proper dismemberment against anything but the most supernatural of weapons and/or opponents is nearly impossible.
So, when I say it acts as a shield, I mean it. You might think getting cut down to the bone would be a problem, but remember: these are vampires. They have an innate regenerative factor. Even among weaker vampires, a cut down to the bone on the arm is a flesh wound that will quickly heal. (Certain things heal faster than others. For instance, while cutting half-way through an arm is a flesh wound, cutting half-way through the waist is most decidedly not.) For stronger vampires, short of supernatural interference in their regeneration, such a wound would heal instantly.
So, basically, they tank the damage on a part of their body which is incredibly resilient (arms are one of the strongest parts of a vampire for many reasons, among them being that vampires use their hands as the primary method of draining blood from their victims/donors so they really need their arms to, you know, still be there), in order to protect more squishy vulnerable parts, then use this interference to create an opening.
The techniques were largely taken from the Zu clan (in particular, Victor Zu), and through their friendship with the Dragul clan, spread to the Darkblood coven, who helped to refine and perfect the technique. However, among the Zu clan, only the elite of the elite know it, and in the Darkblood coven, it's not widely practiced even though many have learned it. The Dragul coven is the coven most known for it, thus, Vlad the Impaler.
I should also note that there are special things about vampires. All immortals have this, but vampires have it in particular, where their spirits change with the passage of time, slowly but surely altered by the material world morphing around them. For instance, while a thousand-year-old vampire's name might not have originally been 'John', it only takes about ten years or so for that name to imprint and override the previous name on a spiritual level. (The exact amount of time is not specific. It could be as little as a day, it could be as much as a hundred years, largely depending on just how much the vampire identifies with that name. If they instantly resonate with it and are like, 'this is me', the change is quicker; if it's just another name to them, it's much slower.)
This is why older vampires, in spite of having perfect memory, tend to 'forget' their original names: even though they have the capacity to recall the name, names tend to lose their significance with the passage of that much time. They usually end up favoring some specific name and/or title, e.g. Lord Darkblood, Oracle, Dracula, and don't have their older names in active memory. They can find said names should they care to, but they don't bother to recall them most of the time, so by all appearances, unless they put the effort into it, they "forget" their other names. Not true memory loss, just memory prioritization, so to speak.
A similar rule actually applies to languages, especially for vampires. They tend to think in whichever language(s) they most commonly are speaking. So even if a vampire was raised 500 years ago in France, if they're in an English-dominated world (which we are), they think in modern English.
Of course, I should also mention: languages evolve, and unless the vampire continues to speak the evolution of the language, their understanding of the language will become dated. So, ability to speak the language 500 years ago does not often translate into ability to speak its modern version. (It works for some, but not many.) They have to re-learn evolved languages just like we do.
And I'd like to also note: while time means different things to an immortal, they do not lose contact with the world as can be portrayed. An innate ability universal in immortals, vampires included, is to slow things down. Maybe things they did 100+ years ago start to blur together depending on the type of immortal, but things they did yesterday are just as clear to them as it would be for us, and same for things they did 5 years ago or even 20 years ago.
This is because, while some things lose their meaning such as their previous, now-non-important names, they still retain important things. Important memories of theirs are permanently imprinted on them. Important feelings of theirs transcend lifetimes. They do not become apathetic; they retain whatever personality they had before they were immortal, and said personality only changes if some event causes it to change, and then that change remains until something else changes it. (This can be time: time can heal wounds for them just like it can for us. However, it rarely is, because if it was a change important enough that their fundamental being was altered, it's probably something only a significant event can change again.)
So, if a person's important, they will be remembered. This applies regardless of whether the immortal has to remember one important person, ten, twenty, two-hundred, two-thousand, two-hundred-thousand, or even two-million. The names are never lost. The people are never lost. They can sometimes fall out of active memory, again because most immortals (including all vampires) have memory prioritization, recalling things as they seem important and otherwise not taking brain power to remember them every waking second, but no immortal will truly forget.
The only way an immortal can forget is if they are either willingly forgetting (this is common in amoral immortals, who simply see no point in dwelling in the past), or have been forced to forget (immortals can be given amnesia in any number of ways, just like people can be). And the only way an immortal can be apathetic is if they already were apathetic or some outside force physically compels them to be that way.