2. Never read a book of Demon Summoning aloud, even as a joke.
3. Do not search the basement, especially if the power has gone out.
4. If children speak to you in Latin or any other language, which they should not know, shoot them immediately. It will save you a lot of grief in the long run. However, it will probably take several rounds to kill them, so be prepared. This also applies to kids whose eyes glow and speak with somebody else's voice.
5. When you have the benefit of numbers, NEVER pair off and go alone.
6. As a general rule, don't solve puzzles that open portals to Hell.
7. Never stand in, on, or above a grave, tomb, or crypt. This would apply to any other house of the dead as well.
8. If you're searching for something that caused a loud noise and find out that it's just the cat, GET THE HELL OUT!
9. If appliances start operating by themselves, do not check for short circuits; just get out!
10. Do not take ANYTHING from the dead.
11. If you find a town which looks deserted, there's probably a good reason for it. Don't stop and look around.
12. Don't fool with recombinant DNA technology unless you're sure you know what you're doing.
13. If you're running from the monster, expect to trip or fall down at least twice, more if you are of the female persuasion. Also note that, despite the fact that you are running and the monster is merely shambling along, it's still moving fast enough to catch up with you.
14. If your companions suddenly begin to exhibit uncharacteristic behavior such as hissing, fascination for blood, glowing eyes, increasing hairiness, and so on, kill them immediately.
15. Stay away from certain geographical locations, some of which are listed here: Amityville, Elm Street, Transylvania, the Bermuda Triangle, or any small town in Maine.
16. If your car runs out of gas at night on a lonely road, do not go to the nearby deserted-looking house to phone for help. If you think that it is strange you ran out of gas because you thought you had most of a tank, shoot yourself instead. You are going to die anyway, and most likely be eaten.
17. Beware of strangers bearing strange tools. For example: chainsaws, staple guns, hedge trimmers, electric carving knives, combines, lawnmowers, butane torches, soldering irons, band saws, or any devices made from deceased companions. (or chipper/shredders, remember Fargo).
18. If you find that your house is built upon a cemetery, now is the time to move in with the in-laws. This also applies to houses that had previous inhabitants who went mad or committed suicide or died in some horrible fashion, or had inhabitants who performed satanic practices in your house.
19. If your parents move you to a town where you find out the high school gym burnt down during Prom night, or hear that a maniac gets loose from a sanitarium every Halloween, then it's time to run away!
20. When trick-or-treating and you come to a house made of gingerbread and gum drops...RUN!! RUN FOR YOUR LIFE!!!
courtesy of Gargor