This guide is a little Dungeons and Dragons centric, but the principles apply well to other games as well.
Letís face it. Although most gamemaster guides will tell you that youíre supposed to be working alongside the players in order to create a fulfilling experience for all, at times itís not possible. Characters get out of hand, players do unbelievably stupid things, or the party simply gets a little too comfortable with their modus operandi. Here are a few simple ways to shake up your players without going overboard.
Truth be told, most players arenít rules lawyers who declare that the Books Are Law and that the dice results are all-important. If youíre going to house-rule and fudge dice rolls, tell your players (though telling them of each instance is not necessary). And more importantly, be willing to do so for both the players and your NPCs. If you insist on playing strictly by the book and not fudging rolls, then be willing to accept that your villainís career may be cut short because the partyís wizard successfully turned him into a dachshund.
Punish stupidity, not misfortune.
Sometimes dice just donít go the playerís way. Donít kill just because bad luck was the deciding factor. For example, if a character rolls multiple failures while using Diplomacy on a foreign king, donít be so quick to have him hanged in the town square (especially if he did a reasonably good job of roleplaying the encounter). However, if that same character rushes the king with sword drawn, feel free to string up the twerp.
Reward hard work and ingenuity, not dumb luck.
Rewards for good roleplaying, unconventional yet plausible solutions, etc. should not be doled out lightly. Whether it's rare items or bonus experience, rewards should be saved for those occasions where brainwork and roleplaying were not only the keys to the party's success, but set a benchmark for the rest of the campaign. However, when these events do happen, make sure the players are rewarded (and told why they are). And likewise with punishment and bad rolls, don't give rewards solely because of good dice rolling or high skill modifiers. If the party's rogue only managed to sneak into the villain's castle because of high Hide and Move Silently skills/rolls, that should not be a cause for celebration.
Take off the kidís gloves.
Whether itís medieval fantasy, alternate-history World War II, or the present day occult scene, most RPG settings are extremely violent places. Be willing to show your players that this setting can be unpleasant. If they insist on solving everything through armed conflict, donít be afraid to personally show them the harsh reality of combat. Perhaps theyíll figure it out by their third character.
Donít be afraid to neutralize your players' special abilities.
If a player is relying on one or two features, one way to get them to rethink their strategies is to render those options unworkable. If a characterís main strengths are in disarming their opponents or breaking their weapons, pit him against skilled unarmed opponents once in a while. If your rogue sneak attacks at every available opportunity, have her fight creatures immune to such attacks. Paladin getting a little smite-happy? Not every opponent has to be evil. Any well-balanced system has ways of dealing with characters who are focused on one thing and one thing only. Naturally, you shouldnít make a habit out of this, but taking a party out of their comfort zone can be an exciting way to make them think out of the box.
Let the players do themselves in.
Destroying a party by sending three red dragons after them is no fun. Destroying a party through backstabbing, intrigue, and deception is much more interesting. Is your partyís paladin a little too anxious to try out magic items? Lay out an amulet that switches alignments, and see how she reacts. Is your partyís prime motivation loot when itís supposed to be justice? Maybe theyíll take a mercenary job from someone whoís secretly under the villainís control. When you employ subtle means such as this, you can rightfully claim that the players had an equal hand in their downfall.
Avoid ďMy game, my law!Ē mentality.
Whether youíre working with the players or against them, nothing kills a game faster than saying things like ďIím god!Ē or ďItís my game!Ē when players donít do as you want . Not only are these statements filled with hubris, theyíre also wrong. Itís their game as much as it is yours. Your rule may be absolute within the confines of a session, but remember that the players have no real obligation to show up each session. And without players, even the best gamemaster is nothing.