Girlinhat has lately been keeping a good tally on the "Vampire Paranoia" scorecard. Toady did a great job with the vampires, after the obvious bugs have been squashed. People are viewing any anomaly in a migrant wave as a possible vampire - this thread is aimed at quelling the rampant myths about vampire detection and telling what actually can be used, as well as what can't.
Vampire Myths
- Animal Jewelry: During worldgen, some historical figures might decide to become big game hunters and travel to remote areas to take down large beasts. They butcher their kills and often make trinkets out of tooth and bone of the animals they kill. Due to the implementation of historical figures as migrants, you'll have those hunters come to your fortress occasionally, often caked in animal bone jewelry. As long as the jewelry is from animals, it's not a vampire, just a good hunter. If the jewelry is from sentient creatures, though... vamp alert.
- Kill Lists: You'll often see migrants with kill lists in their histories. Vamps try to mask their bloodsucker kills. Kill lists on hunter migrants (see above) will often be things like tigers and giant hamsters. Historical soldiers will sometimes also have dwarf, elf, and goblin kill lists. That means a soldier, not a vampire.
- High Social Skills: People often associate high social skills with being a vampire. Although vamps do often have high social skills, sometimes vampires do not. As well, many, many, normal dwarves will end up with high social skills during worldgen and migration or while at your fortress.
Vampire Facts
- Sentient Jewelry: Check migrants for +Dwarf Bone Earrings+ or other similar sentient jewelry. Unlike simple animal jewelry, that marks a vampire.
- Relationships: Vampires will mask their family history. In well-established forts, most dwarves have at least a second-great-niece somewhere in the fort. Checking the (r)elationships of a dwarf can show if a dwarf has no living relatives in a strong fort where dwarves are normally related, that can mark a vampire.
- Entity Histories: Check for long blue lists of "He was a former member of X government" repeated 20 times. Vampires are always on the run during worldgen, and they do not always mask their histories of living in former towns.
- Drowning, Eating, Drinking, Sleeping: Vamps do none of these. Although vamps don't drown, they won't path through water, and therefore you can not make a simple vamp detection system. Hospitalized vampires WILL sleep in a hospital bed, but it is a kind of sleep called 'rest' that even vampires can do.
I probably left out a few entries in both sections, so feel free to comment and discuss, and spread to people who keep asking the easily searchable questions in new threads.