How To Be a Bad DM

You'll be seeing a lot of these echoed in my more specific posts, but I don't think it diminishes their value.  Also, I'm sure there are lists like this one out there somewhere, but this one is mine.

• Compete against the players.  Gloat when you destroy them and curse them for their incompetence afterwards.  Extend your pleasure by never letting them forget the past.

• Get cocky players out of their comfort zone by designing encounters to thwart them.  Repeat this mercilessly.  For added bonus, negate player characters' powers arbitrarily and without warning.

• Complicate trivial tasks, but still give trivial rewards. While you're at it, just don't reward the players for anything.

• Encumber players' characters with campaign specific restrictions.  Things will be much more interesting when the wizard's spells only work under a full moon.

• Make it impossible to the players to make characters with the race/class combination they want.  If you do let them have it, correct that mistake by forcing them to change it later with a contrived plot device.

• Ensure your NPCs are much cooler than the player characters and give those NPCs the spotlight as often as possible.  Use these NPCs as irresistible adventure hooks by bullying the players' characters into submission.  Have this NPC steal their kills, but withhold aid when its really needed.

• Make frequent rules changes, especially if they limit player's options.  However, remain completely inflexible about game rules that irritate the players.

• Don't bother preparing anything before game time.  Don't bother knowing the rules, either.  Just make everything up as you go, but be sure not to take notes---that way you can be inconsistent, too.

• Unleash your emotions.  Become furious or hopelessly depressed whenever the players accomplish something you didn't expect.  Being drunk helps.

• Pick one of the players, preferably an obnoxious one.  Only make eye contact with that player.  Favor that player's character in every possible way.

• Pick another player, preferably a shy one.  Use your divine power to doom that player's character to fail at everything.  For added effect, frequently put that player on the spot and berate that player whenever any undesirable thing happens.

• Punish the players for their successes.  Completing mission goals and overcoming difficult challenges should make their lives much harder.

If you have any suggestions, feel free to contribute.  I doubt I've given everything you need to be the worst DM you can be!