When it appears you have killed the monster, NEVER check to see if it's really dead.
Never read a book of demon summoning aloud, even as a joke.
Do not go search for something in the basement, especially if the power has just gone out.
If your children speak to you in Latin or any other language which they should not speak, or if they speak to you using a voice which is not their own, shoot them immediately. It will save you the grief in the long run. *NOTE* It will probably take several rounds to kill them, so be prepared.
When you have the benefit of numbers, NEVER pair off or go alone.
As a general rule, don't solve puzzles that open portals to Hell.
Never stand in, on, above, below, beside or anywhere near a grave, tomb, crypt, mausoleum or any other house of the dead.
If you are searching for something which caused a loud noise and you find out it's just the cat, leave the room immediatey if you value your life.
If appliances start operating by themselves, move out.
Do not take *anything* from the dead.
If you find a town which looks deserted, it's probably for a good reason. Take the hint and stay away.
Do not fool around with recombinant DNA technology unless you're sure you know what you are doing.
If you're running away 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 c...