Villains who are evil just because they're evil are rare. They also tend to be boring. A really good villain has a motivation for being evil... some even have two or three. Here are some of the most common:
- Spread Hate and Fear: Some villains want to make the world a little bit worse. Marvel Comics has a villain called the Hate-Monger who tries to spread hate and bigotry. By the time the heroes arrive to stop him, there are riots in the streets and the city is in flames. This is an excellent goal for low-powered supervillains in politically-themed campaigns. If your campaign is inspired by Watchmen, add a Hate-Monger villain.
- Corrupt Everyone: This is a similar goal. The villain works on individuals, usually powerful people. He exploits their weaknesses. He works behind the scenes to corrupt the kind-hearted and indulge the mean-spirited. This is the motivation of Marvel Comic's Mephisto, a character based on the devil.
- Control the Kids: ...or any other vulnerable segment of the population. The villain wants an army of puppets and zombies, people who will carry out his orders in secret and in concert. He can use some kind of psychic power, weird science (a Kirby-inspired Mega-Mind-Dominator Blaster), or he could drug the water supply. In the 1960s, a villain would use drugs or television to control peacenik college students, a not-too-subtle comment on the protests of the time.
- "Leave Me in Peace!": The villain wants to be left alone, but something (or someone) drags him into the campaign. When he is pushed too far, he attacks. Usually, the villain has cosmic powers — and a cosmic lifestyle. The Gardener (from Marvel, again) was content to tend his gardens on other planets until he became involved in some superhero's adventures. Then he would use his extensive powers to drive the superhero away. Galactus falls into this category, believe it or not. He just wanted to live in his big spherical spaceship and eat entire worlds when he was hungry. As long as the heroes left him alone, he was content. When they tried to stop him, he kicked their asses. But he really meant no harm.
- Regain What Is Lost: The villain is on a quest for a missing lover, relative, or object. Or, he might be searching for his homeland and brethren. He may want to regain his lost humanity. As long as no hero, group of people, or place stands in his way, everything's okay. But when the villain decides that the world stands between him and his goal, it's time for the heroes to get involved.
- Save Humanity: In Watchmen, Adrian Veidt wanted to end the standoff between the United States and Russia for the benefit of mankind. His methods required many crimes, both personal and political, so he was rightfully regarded as a villain. His goal was admirable, but the heroes didn't think the end justified the means. This type of motive is complex and worth exploring with a series of adventures. The heroes will have to decide whether or not the villain really is villainous; each crime will have to be considered in its context. Of course, if they don't discover the goal until the final adventure, this sort of introspection won't come up until the climax of the campaign. A variant of this motive is the villain who says he wants to save humanity but he's really just a dangerous nutcase. Like the mastermind in the James Bond film Moonraker, he has that "My Lai Massacre" mentality: "We had to destroy the village to save it". Or, he might save mankind by forcing them to behave correctly... when, of course, his version of "correct" is very disturbing.
- Get Rich: This is the classic goal of Batman's recurring foes. All too often, a goofy villain like the Penguin or the Riddler or Catwoman wanted to steal something from a museum and sell it to the highest bidder. Or rob a bank. Or extort a million dollars from Commissioner Gordon. Could there be a less creative goal for a villain? No. It is possible this came up a lot with Batman's villains because they were all so light on superpowers — if your claim to fame is a skintight green suit and an obsession with riddles, you're limited this kind of cheesy villainy.
- Serve the Fuhrer: Even the greatest criminal minds will bow to a higher power. The Red Skull, for example, was smarter and more capable than Adolph Hitler ever dreamed of being, but he served his master nonetheless (even when the Fuhrer was dead). A villain with this motivation might serve someone (or some force) that no one else ever sees. That could be half the fun in the adventure... trying to find the ringleader.
- Revenge: The villain wants revenge against a hero, maybe one of the PCs. He has to defend his honor, or his sister was accidentally killed in the crossfire, or he's been disfigured. Dr. Doom and Baron Mordo had rivalries with Reed Richards and Dr. Strange, respectively, based primarily on jealousy and revenge. (And there was a time when Lex Luthor blamed his baldness on Superman. Ouch! You'd think a guy as rich as The Double L would just get plugs and leave the Man of Steel alone. Talk about insecure...)
- Ruin a Hero: This is like revenge, except the villain wants to ruin the life of a particular hero (or hero team). In the late 1980s, there was a villain named Sleez who tried to film Superman in a porno with a female hero named Big Barda. (It's true! It was back in the John Byrne Action Comics days.) Sleez was a green, reptilian guy who lived in the sewers. All he wanted to do was ruin Superman's reputation. (You're thinking about Superman naked right now, aren't you? SHAME ON YOU!) Instead of defaming a hero, the villain might try to eliminate the hero's superpowers... or make the hero evil.
- Annihilate! Raze! Lay Waste!: The easiest and craziest motive is to just destroy everything. This is a villain who doesn't care about the minds of men, money, or revenge. He just wants to see the world blow up as soon as possible. The alternate version is a villain who wants to destroy one thing. That one thing has to be something near and dear to other people, something the heroes feel is worthy of protection. It could be a place, a powerful artifact, or a person. Or the moon.
- Personal Power: On the way to a greater goal, many villains will try to increase their superpowers, enlarge their resources, gain new followers, or find the key to immortality. Once the heroes get wind of this, they will try to intervene to avoid a stronger, tougher opponent the next time he tries to take over the world. The best example is the old Avengers comic in which they battled Count Nefaria. The Count became so overwhelmingly powerful, the Avengers didn't wait until he did something nefarious. If they waited, it would be too late. If the heroes aren't likely to catch wind of the villain's scheme, link the villain's increase in power directly to the heroes. Maybe he has to steal something from them, drain their powers, or get vital information from one of their sidekicks. This tips off the heroes.
- Win the War: This is the quintessential goal of the Nazi supervillains: they were really just weapons in the Fuhrer's army. Their purpose in life was to conquer Europe, destroy Russia, destroy Britain, and generally usher in the Thousand-Year Reich. This goal is always available because there is always a war going on. The Cold War lasted from the end of World War II to the late 1980s, so there is plenty of room for villains (and heroes) whose sole purpose in life is to eliminate or cripple the enemy. In the meantime, there are other wars around the globe for villains to serve.
- Rule Part of the World: The villain wants to take control of New York, a small country in Eastern Europe, London, the Pacific Ocean, and so on. He's too smart to think he can take over the whole world. He'd rather be Supreme Dictator of a large chunk of it. Sometimes this motive seems legitimate. Dr. Doom was the dictator of a small (fictional) country called Latveria. Although the Fantastic Four didn't want Doom controlling a small country, it didn't seem right to fly in, kick his ass, and leave. What if Doom was replaced by an even worse dictator? What if the Latverians liked Doom?
- Rule the World: Last but not least, what's so bad about being Supreme Global Dictator? Every villain with this goal has to reconfigure the world politically so it will serve a central dictator. That's half the problem, figuring out how to get everyone to obey you after you've killed all the superheroes. Every would-be world-ruler has to have a plan, a scheme that explains how everyone will be forced to do what he says. The best villains of this kind will also have a plan for making that dictatorship permanent... once he wins, that's it for humanity. Ruling the world has a lot of fringe benefits (like increased superpowers for those villains who feed off of other people's life force), but most villains of this type are in it for the power. No drug or orgasm compares to the knowledge that you control everyone and everything on the planet. That's why these villains tend to be half-crazed the moment they arrive on the scene... just the anticipation of total power is enough to make them overconfident, megalomaniacal, and delusional.