This post is the official announcement of the completion of the first stage of the Great Slasher Research Project of 2010!
We had more than 50 sources - ranging from scholarly texts to trait lists submitted by readers - who came up with 43 distinct traits that define the slasher movie subgenre.
Taking the most consistent identified traits, here are the elements that we've collectively decided define the subgenre, in order of votes:
1. Single or small group of human killers
2. Multiple kills
3. Killer exhibits focused hunting/stalking behavior
4. Pre-selected victim pool, determined by victim trait or location
5. Succession of kills over time
6. Killer was wronged or has a tragic past
7. Killer uses personal, low-tech weapons (no traps, guns, bombs, poisons)
8. Killer's identity is a secret
9. Final survivor or small group of survivors fight against the killer
10. Predictable order of kills determined by victim traits
Notably, the final girl and the predictable victim order, both common tropes in horror criticism and meta treatments of the subgenre, just barely made the cut.
Thanks to everybody who helped out. I'll be announcing the second part of our research project - and how you can help - shortly. Stay tuned, fright fanciers.