It’s a harmless-looking, friendly group. Granted, these people aren’t average-looking–some of them are dressed as medieval princesses and alien lords. The less outrageous ones sport T-shirts bearing thoughts such as “Outside of a dog, a book is man’s best friend. Inside of a dog, it’s too hard to read– Groucho Marx.”

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A woman named Lisa Freitag–someone who appears more likely to lecture on interior decoration than mayhem–steps to the front of the room. She’s a doctor from Okana, Minnesota, who doubles as a consultant to science fiction writers. She ignores the podium and instead sits cross-legged on one of the front tables. “I’m Lisa Freitag, and I’m a real doctor,” she proclaims, and launches into her spiel.

“One researcher I knew spent nine months in a library researching pirates. But then he had his character get knocked out on the head for two days, then get up and run around. People, this just doesn’t happen!” she shouts.

“The two ways you can do people in are by messing up their brain or hitting their heart and blood vessels,” she says. Any other injuries are slower to cause death. “You can have blood leaking out in various proportions, depending on how long [you want it to take] for your character to die. If you need a 15-minute protracted bleeding, the blood goes slow. If you need them to die close to instantly, you can do that. You can–and should–change the location of the wound to determine how fast the injury takes effect.

The man in the Groucho T-shirt asks, “What about a puncture wound to the back of the thigh? My character rinsed it out with alcohol, then had a fever and red wounds, but was up in about a month and a half.”

“It takes about three minutes.”

Freitag continues her anatomical tour. “The shoulders are enormously well protected. Granted, if I had a dislocated shoulder, I wouldn’t be able to use it right away, and neither would you, but we’ll give Mel Gibson the benefit of the doubt.”