It's a pretty sorry excuse for a GM to rationalize his antagonist's actions with the words; "He's evil!" Nope. Not buying it. For every action that is perceived as either evil or good there is motivation behind it; and the best villains believe what they're doing is good.
This is my largest problem with all of the alignment systems out there. Largely due to the fact that perceptions of what is good and what is evil vary. Most people believe what they're doing is either good or for the greater good, at least initially. Mad scientists believe they're advancing science. Politicians go in hoping to make some changes. Then a little change begins, the mad scientists doesn't realize he's crossed the line and is surprised when the townspeople begin mobbing his home. Politicians can't take the bureaucracy, but don't want to give up the power or lifestyle that they've gained. There's always motivation behind their actions.
Every non-player character presented by the GM in a game should have some motivation for their actions. This doesn't mean that the GM should go create a life-chart for every NPC, but if a non-player character approaches the PCs or a PC there should be a reason why. The fact that the NPC is "good" and the PCs are "good" is not a reason.
This holds true especially for the main antagonist of a campaign. The GM should have a detailed idea of why the antagonist is doing what he is doing. Power, be it political, supernatural or physical, is normally the reason most GMs give, especially for the main antagonist. Power to what end though? Very few people seek power for the sake of power. What pushes the antagonist in doing what he's doing for the thankless job of being king, for instance? It could be something as simple as becoming king to help his homeland, which has become over-taxed and destitute, to a snowball of reasons, beginning with the character's abuse at home.
Sure, it's fun and easy for the PCs to kick down the door and in one way or another slaughter the "Evil NPC", but think of the life it could bring to the game if the PCs confronted the antagonist and realized his actions were justified in some way. This leads to the expansion of the game. The PCs might decide to assist the NPC in what was once thought of as his "evil plan", or they may figure out a better way to solve the NPCs problem.
Of course, they could hear the NPCs story and decide to put a bullet, or sword, etc. between the eyes of the antagonist. But then, you might want to question the PCs on their motivation.
That's right, players, just as it's true for the NPCs the PCs should also have some sort of motivation for going out and doing "good". This is generally provided by the GM as some sort of hook. But, as I stated in one of my earlier columns, the players have a responsibility to look for the hooks presented or perhaps create some of their own.
Adding the motivation behind the character gives more dimension to the character, and can lengthen the life span of the campaign to eternal proportions. And that is definitely good gaming!
-Roll saving throw vs. Bad Gaming!
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