Since before the first Monster Manual, dragons were designed to be the ubiquitous challenge of D&D. They were in the name, after all. So it was only natural that Ravenloft, a setting where dragons were scarce and the iconic critter was the bloodsucking vampire, introduced vampire subspecies and age categories. Vampires were the new dragons: iconic foes with sufficient variety so that the DM could scale them to be a challenge for a party of any level. Subsequent editions added vampire spawn and templates for the same reason.
But Ravenloft is also about foes with backstory, which doesn't always match up with traditional scaling methods. Suppose you want your 3rd level party to fight a vampire, but Joe Peasant (as a spawn) doesn't fit the bill? What if your PC pick a fight against a known vampire that would normally be too powerful for them? What if a later story demands a reasonable excuse for how they ran afoul of a centuries-old nosferatu and lived to tell the tale?
When dealing with an imbalance of power, it pays to know your classics, and this concept has been written about for centuries. "The Art of War" states that when waging war against a more powerful foe, it is critical that you control the time and the place of the fight, and wait for the right moment. Sun Tsu may not have been a gamer, but when it comes to vampires, it turns out he was especially accurate: vampires have special weaknesses when it comes to timing and placement. If your PC's are below the level where they might survive a standard toe-to-toe, consider giving them one of these forms of good luck.
1) Let Sleeping Vamps Lie
As Jander Sunstar said to Strahd Von Zarovich, "One peasant with a planting stick is more than a match for you during the day." It's a classic trope of vampire hunts for the PC's to explore the crypt while the sun shines, facing traps and tricks and guardians only to find the creature's resting place as the sun is setting. It's no crime against narrative to allow low-level PC's to face fewer traps and guardians and actually get there in time to stake the monster in the coffin. Or you might reverse the idea, letting them stumble into the creature's path just after midnight when it is active, and let them figure out ways to stall and hide and evade until they run out of options...and are rescued by the rising sun.
2) Burning Daylight
Of course, the other think about daylight is, well, the light. Apart from nosferatu, who merely lose their supernatural powers, sunlight destroys vampires more effectively than anything, and they know it. Even a first level party stands a decent chance of surviving if the creature has been forced to take shelter in the shadow of a tall tree or tower at noonday. Forced to forgo sleep to keep moving, only a narrow band of shadow between it and oblivion as the day marches on, it could tear to pieces anyone who comes too close, but a low-level party that avoids eye contact might engage in a prolonged battle of wits that gives new meaning to "burning daylight."
3) Location, Location, Location
While some vampires may tolerate the sunlight for a brief time to escape the PC's, hardly any can ignore the restriction on entering residences uninvited. According to Van Richten's Guide to vampires, only those who normally reside in a place can issue a proper invitation. To give a first level group a strategic advantage against a vampire, let them encounter it seeking entrance to a place where they are guests. Not knowing who is a resident, the creature dominates a PC or NPC guest for an invitation, but still cannot enter. The rest of the party figures out there is something unusual going on as the dominated PC tries to secure an invitation from an actual resident, with the vampire pacing on the doorstep in frustration. The party will get a good challenge out of fighting the dominated character (and perhaps some summoned animals) before the creature moves on to easier pickings.
4) Death Takes a Holiday
Restricted as they are by their requirements for blood and sleep, vampires are not prone to travel. Those who undertake a long journey must bring their coffins with them, and those without loyal quislings to haul them in a wagon frequently find themselves stowed in the hold of a boat. This is not in itself a violation of the prohibition against crossing running water...but the creature cannot leave the boat except to set foot on land. This is easily compounded by the above restrictions on sleep, sunlight and invitations: passenger staterooms are not separate residences, but crew quarters are. If passengers are few, a vampire might be forced to choose between gaining a new invitation every night so it can shallow feed, or risk arousing suspicion by feeding from the same people twice. Count Dracula himself was forced to depopulate the entire crew of a ship one by one to make the journey to England. If only one of those crew had knowledge of vampires, and could explain to the others how to hold them off, that ocean voyage might have ended much differently.
So that’s four ways your low-level PC’s might gain the upper hand against a vampire, but then what? If the creature escapes, it will surely have a long memory of its defeat, and it will never allow itself to be caught in such circumstances again. If the PC’s managed to destroy it for good, it may have had a mate, sire or spawn that would likewise hold a grudge. Allow the PC’s their moment to lick their wounds and pat themselves on the back, but they had better not count on luck next time. Luck is a fickle ally, and you never know when the forces that tipped the scales for you might side with the monsters instead.
Matthew Barrett has been playing and writing for Ravenloft for over twenty years, starting with the Kargatane's Book of S series (as Leyshon Campbell). He married his wife on Friday the 13th after proposing to her on Halloween. By tradition, the first story read at birth to each of their three children was The Barker’s Tour, from Ravenloft’s “Carnival” supplement. He is currently working on a Ravenloft-based experiment in crowdsourced fiction using his “Inkubator” system at inkubator.miraheze.org.
Image is from Ravenloft 3.5 and is titled Races of Ravenloft
I am become death, destroyer of worlds.