Without further ado... here's How to Think Like a Vampire (or Ghoul):
Part One: The Blood Is the Life
It's simple and obvious to say that, to a vampire, blood is everything. But to consider what this truly means, and to apply it to the way your character thinks on a moment to moment basis, is rather more complicated.
Do you know what it's like to struggle with an addiction? If so, channeling that knowledge into a vampire character can be cathartic. To understand what it's like to be a vampire who has to go without blood, combine all of the worst symptoms of heroin withdrawal with the clawing, screaming, helpless abject terror of being buried alive--that will serve as a rough approximation of every aching, miserable second that your Vitae pool is 2 or less. A starving vampire is a rabid, cornered animal that would eat its own mother without the slightest hesitation.
But having more Vitae in your system doesn't shut that off; it merely turns down the volume a little bit. If vampires were only affected by their addiction when they were hungry, they would only be monsters when they failed to keep fed. The full truth is that vampires are monsters all the time, because for the addict, the addiction is a constant background force and can never be sated or cured. Whether your most recent fix was two days, two hours, or two minutes ago, it doesn't matter--your every thought and every decision are motivated by getting the next one. Rationalizing the need. Planning the next score. Trying (failing) to avoid the temptation. Covering up what you've done, or will have to do.
Inevitably, addicts damage their relationships with others, because these relationships are only bothered with to the point that they serve the addiction. If you're a truly hopeless junkie, you never call your friend just to say hello or to catch up. You call because your friend is a line to your dealer, or because you need to borrow twenty bucks. To the slave of an addiction, people are just tools.
All vampires--ALL OF THEM--are a worse version of this type of junkie. A vampire is a predator to whom humans are prey. To a vampire, none of the usual human needs even exist, because vampires are not human. Friendship? Companionship? Love? Aesthetic beauty? Vampires DO NOT FEEL THESE THINGS. Oh, sure, they approximate and imitate them. Most of them tell themselves they still have a human side. But while they fool others, and frequently themselves, into thinking they feel them, they do this for precisely the same reason that a polar bear's fur is white: camouflage. That's it.
This is why every artist who is Embraced ultimately stagnantes, by the way. They can't innovate--they can only approximate what they did while they were alive. And the same goes for every other aspect of human life. Every vampire who seems nice? Faking.
To a vampire, blood is everything. Literally everything. Every vampire is, by definiton, a compulsive sociopath who is at best one step removed from desperate, murderous hunger. It is impossible for a vampire to be a good person. It is impossible for a vampire to feel compassion, empathy, or real concern for another living being. It is impossible for a vampire to love someone. And it is impossible to play a vampire accurately until you accept these facts.
Part Two: The Danse Macabre Exists Because the Definition of "Risk" Changes When You're Immortal
As a general rule, the more a person has to lose, the less willing that person is to take risks. When you consider the implications this has for a person of potentially infinite age, it's easy to understand why most vampires--especially the ones who live long enough to become Elders--are actually massive cowards. If you're up against, say, an angry werewolf, why risk fighting? A werewolf has a limited lifespan. Successfully avoid it for long enough, and your problem will simply go away.
Of course, it's often not that simple. Problems like angry werewolves have a way of finding you if all you do is sit back. But, as the saying goes, if you and your friend are being chased by a bear, you don't have to outrun the bear--you only have to outrun your friend. And this is where being a compulsive sociopath comes in handy.
For an immortal, unfeeling creature like a vampire, throwing yourself into combat with an enemy is horrifically illogical except as a last resort--it's infinitely better to find some dupe to fight your battle for you. Who cares if your thrall stands no realistic chance of killing that werewolf that's got your scent? Thralls are cheap--make more. Every day that your werewolf spends distracted by your servants is another day along that werewolf's journey toward an inevitable death.
Vampires are masters of proxy warfare. Every smart vampire uses intermediaries, and the very best of them are so good at it that their enemies don't even know who they are actually fighting. The werewolf dispatches a cleverly-placed thrall, ghoul, or childe, assumes that the hunt is over, and in his ignorance concedes to his true foe inevitable victory.
It's important to know which minion to deploy to which task. Less is typically more. Sometimes throwing some money (the most expendable resource of all) at a clueless human is sufficient. Sometimes a little blood is needed to really make them want to serve. Sometimes a more dedicated and powerful servant like a ghoul is just the thing. But sometimes what you really need is another Kindred--and this, when you get down to it, is both the sole reason any sane Kindred ever Embraces anyone, and the entire cause of that endless cat's-cradle of scheming people call the Danse Macabre.
And that's why the Danse exists and persists. It's not some game a bunch of immortals are playing because they're bored. It's how vampires prosecute conflict. It's how they survive and thrive. It's essential to their existence.
Part Three: A Vampire's Tools: Disciplines and The Vinculum
You might think that, based on the above, the Ventrue and Daeva Clans have a leg up on everybody else. You might think, sure, this Danse Macabre stuff sounds great for the two social Clans With Dominate and Majesty at their disposal--they have an easy time manipulating humans, and can use their servants as their weapons. But the lowly Gangrel, Mekhet, and Nosferatu still have to do things the old fashioned way, right?
Well...no, actually. Dominate and Majesty are amazing, but Gangrel and Nosferatu are arguably even better at proxy warfare than Daeva and Ventrue are.
Remember what I said earlier about avoiding one's problems until they go away? Well, how are you going to find a vampire who has that first dot of Obfuscate or Protean? These powers cost nothing and allow a Kindred to become practically undetectable. Obfuscate means a vampire who doesn't want to be found is forever just a face in the crowd, and even a supernaturally-gifted tracker like a werewolf is going to be confounded when the vampire's trail simply disappears at an innocuous patch of ground. Of course it only gets better from there. The terror of Nightmare can be just as compelling a manipulation tool as the charm of Majesty in the right hands, and the servants one comes by through Animalism--the most underrated Discipline in the game--are often more reliable and predictable than human proxies.
Basically, regardless of your Clan or abilities, you need to realize that every vampire is doing the same thing, and that every Clan's Disciplines are geared toward the same ends, which are the same ends of any predatory creature:
1) Find food.
2) Don't get caught.
More importantly than that, regardless of Clan, every vampire has access to one tool which is far and away more useful than any other: the Blood Bond.
Creating a thrall is incredibly easy and requires almost no investment on the part of the vampire. Force or compel a human to drink vampire blood three times on three occasions and that person will pretty much do whatever you say, forever. A thrall is an excellent disposable resource, good for a reliable meal and great for proxy warfare. Send them--wittingly or not--to do your bidding against your enemies. Keep them clueless and/or totally misinformed. Let them (trick them, make them) take insane risks on your behalf, because when they die you'll be safe in the knowledge that they'll stop pestering you for blood and that they didn't rat you out. Smart vampires use and abuse thralls.
Of course, if you want a more regular and more reliable servant, you can invest a little more time and energy into creating a Ghoul. A ghoul is a miserable creature which becomes more and more dependent on you for the longer you keep it as a pet. At first, it's just the thrill of Vitae and the (fake, forced) love of the Vinculum. But eventually a ghoul realizes that their power and immortality are contingent upon their continued service to you. A ghoul who has been in that state for a century is very well aware that even one missed dose means more or less instant death.
Ghouls are fantastic proxies for taking care of everything from mundane paperwork to daytime assassination. You've just found out where your Kindred arch-nemesis keeps his haven? Give your ghoul a wooden stake and a can of gasoline--you go to sleep at dawn, and wake up at sunset to a nemesis-free existence, or if your ghoul dies in the attempt you just make another one. Animal ghouls are in some ways even more reliable, and depending on the species make excellent bodyguards, spies, and trackers. Smart vampires keep at least a ghoul or two and work hard to maintain them--although these servants' best quality is still the fact that they are expendable.
Part Four: Playing the Blood Bond
Pity the wretch who is blood-bound to a vampire--even if that wretch is another vampire.
The Vinculum is a perverse, twisted corruption, a torturously decadent and above all FAKE approximation of love. It's worth emphasizing the word "fake" here. The love the Vinculum makes you feel is fake, forced, and wrong. Subjecting someone to the blood bond is basically rape. It's arguably worse than rape, because it's domination of the mind and self rather than merely the body.
Have you ever known someone who was in love with a person who was clearly bad for them? People in abusive relationships will often find all manner of ways to rationalize staying in them, to try to twist things to whatever angle will allow them to convince themselves that their abuser is better than they look, better than everyone else says. You don't see what I see. He's not like that all the time. It's my fault. He's only like that when I mess up.
The constant string of excuses and self-deception created by the blood bond is essentially a result of the victim's total dependency on the Vitae. It's not love. It's Stockholm Syndrome. It's desperate rationalization in the face of addiction. And where it does resemble love, it's all the worst parts. Irrational possessiveness. Frenzied jealousy. The violence of unchecked feeling.
Some vampires trick themselves into thinking that the Vinculum is a way to increase their sensation. If they can't feel authentic human love, they figure, this is the closest approximation. They're not wrong, but that kind of thinking rarely ends well. Relationships change, but the burning need of the Vinculum doesn't.
In this sense, ghouls have it the worst of all, because unlike vampires they're not emotionally dead inside. Ghouls DO have feelings, often very strong ones, and the Vinculum wreaks absolute havoc on a human being's emotional balance. Hate and love, desire and revulsion, fascination and fear--they all start to blend together as a human's natural instinct to recoil from a supernatural predator is subjugated by the screaming will built into the Kindred's blood.
Most ghouls grow to hate their regnants, because all regnants abuse their ghouls. Abuse doesn't have to take the form of verbal insults or physical battering. Some vampires--most of them, in fact--are very NICE to their ghouls, at least on a surface level. The abuse comes in the trauma that a servant to a vampire inevitably experiences, regardless of the Kindred's intention. Ghouls have to expose themselves to horrific experiences in the service of a vampire, and as time wears on and these experiences pile up they will ultimately associate this continued trauma with their masters.
But despite growing to hate their regnants, ghouls are powerless to do anything about it. All negative thoughts about the regnant are buried under a tidal wave of desperate, fawning rationalization. The ghoul might unconsciously want to murder her regnant, and put an end to this torment, but will find herself simply unable to do so. This kind of juxtaposition is the path to madness.
So while ghouls will loyally serve their regnants, they will often find ways to vent the energy of this horrible internal conflict by acting out in other aspects of their lives. They pile more addictions--drugs, booze, thrill-seeking, sex--onto their need for Vitae as a way to try to blunt the pain of the latter. They stalk their regnants obsessively in a misguided effort to "protect" them. They misbehave on purpose, provoking punishment from their regnants, because even abusive attention is better than no attention. They project their hatred of their regnants onto others, lashing out at softer targets or at totally innocent people. They take suicidal risks, ostensibly to impress their masters, but just as likely out of subconscious need to put an end to their own misery.
If the vampire is the cold-blooded, methodical killer, then the ghoul is the hot-blooded killer who creates a bloodbath in a fit of deranged passion and then, with a sigh of relief, blows his own brains out.