The hardest character to create is the nemesis. Some comics do it right, while others don't even bother. Making it weirder is that some comics have created entire teams of great nemeses for their heroes, and each one works, sometimes against other heroes, while some of them work even against other nemeses. There are some basics to consider when you create a nemesis for your characters.
The Anti-Theme: Some comics have a very definite theme, and the hero tends to be the paragon of that theme. The Anti-Theme is a character that represents the other side; if the theme of the comic is "family is important", this is the guy that works alone and sees family as a weakness. If the theme is "war is bad", this is a gung-ho Marine. Although he may start off as weak, he should get stronger as the heroes do. It needs to be noted that this nemesis isn't necessarily a bad guy; he just has a different perspective than the heroes. This means that he also team-ups the most of any villain with the heroes; sometimes the heroes just need that perspective. If the theme of Spider-man is that of family, as well as that science is good for humanity, then this is why The Lizard and Doctor Octopus are great nemeses: The Lizard is also a family man, but with a dysfunctional one, while Doc Ock is from the "science is good for ME" side of the coin.
Alpha Villain: The hero is usually seen as the Top Dog of his universe, however that universe is defined. For some heroes this instills a certain noblesse oblige, such as with Superman: He is the most powerful person, so he has to do the most good. Others see themselves as the Supreme Policeman, responsible for protecting their area: Batman protects Gotham CIty from the worst of the worst. When you look at their nemeses, the best are after their spot, albeit from a different perspective: Luthor also seeks to be the hero, even though he is after it for personal reasons. The Council of Owls wants to protect Gotham City, but that's because they want to monopolize all of the power. A good nemesis has the same goals as his respective hero, but they are twisted a bit.
The Opposite Number: In some cases, the nemesis is virtually identical to the hero, except for their goals. Doctor Doom is the best example of this, as he and Reed Richards are so close. Batman seems to have acquired a number of these: A decent subset of his villains, such as Hush, Anarchy, even Catman, are humans that have pushed themselves beyond normal human limits, but for personal reasons, such as revenge, serving chaos, even to simply test themselves. These nemeses work because they show how the hero could have turned out had circumstances been different. It's not only a great way to explore the character, but if the villain starts taking on the beliefs of the hero you have a great new character, even one that could replace the hero.
The Mistake: Every hero has that one villain created because he screwed up. With Batman you have The Joker, who was the result of being pushed into a vat of chemicals by Batman. Professor X has The Juggernaut, who he made the mistake of showing his power by revealing he knew Cain Marko's secret shame. This character is great because he shows that the character is capable of mistakes at the same level of his powers, and how he deals with that mistake shows a lot about who he is.
The Competitor: Of course, occasionally you have that nemesis who is all about the competition, and that's it. He's not really a villain, and he may have nothing in common with the hero past he sees the hero as one of the greatest challenges of his career. Kraven the Hunter is the best example here: He sees Spider-man as a worthy foe, and therefore someone he needs to defeat. This is villain is different from the rest in that good and evil doesn't really apply to him; he can ally with the villains or hero, and it doesn't come off as forced. The character may even be a hero is his own right, he just likes messing with the hero as a sort of progress check on his own abilities.
Above all, remember to have some fun creating the Big Bad. It's a cliche, but your heroes are only as good as their villains, so make your villains as nasty as you possibly can. This is definitely an area you can have some fun with, so take full advantage of that. Do it wrong, and the villain fades into mists of memory; do it right, however, and you could have one of the most memorable characters ever!
The Anti-Theme: Some comics have a very definite theme, and the hero tends to be the paragon of that theme. The Anti-Theme is a character that represents the other side; if the theme of the comic is "family is important", this is the guy that works alone and sees family as a weakness. If the theme is "war is bad", this is a gung-ho Marine. Although he may start off as weak, he should get stronger as the heroes do. It needs to be noted that this nemesis isn't necessarily a bad guy; he just has a different perspective than the heroes. This means that he also team-ups the most of any villain with the heroes; sometimes the heroes just need that perspective. If the theme of Spider-man is that of family, as well as that science is good for humanity, then this is why The Lizard and Doctor Octopus are great nemeses: The Lizard is also a family man, but with a dysfunctional one, while Doc Ock is from the "science is good for ME" side of the coin.
Alpha Villain: The hero is usually seen as the Top Dog of his universe, however that universe is defined. For some heroes this instills a certain noblesse oblige, such as with Superman: He is the most powerful person, so he has to do the most good. Others see themselves as the Supreme Policeman, responsible for protecting their area: Batman protects Gotham CIty from the worst of the worst. When you look at their nemeses, the best are after their spot, albeit from a different perspective: Luthor also seeks to be the hero, even though he is after it for personal reasons. The Council of Owls wants to protect Gotham City, but that's because they want to monopolize all of the power. A good nemesis has the same goals as his respective hero, but they are twisted a bit.
The Opposite Number: In some cases, the nemesis is virtually identical to the hero, except for their goals. Doctor Doom is the best example of this, as he and Reed Richards are so close. Batman seems to have acquired a number of these: A decent subset of his villains, such as Hush, Anarchy, even Catman, are humans that have pushed themselves beyond normal human limits, but for personal reasons, such as revenge, serving chaos, even to simply test themselves. These nemeses work because they show how the hero could have turned out had circumstances been different. It's not only a great way to explore the character, but if the villain starts taking on the beliefs of the hero you have a great new character, even one that could replace the hero.
The Mistake: Every hero has that one villain created because he screwed up. With Batman you have The Joker, who was the result of being pushed into a vat of chemicals by Batman. Professor X has The Juggernaut, who he made the mistake of showing his power by revealing he knew Cain Marko's secret shame. This character is great because he shows that the character is capable of mistakes at the same level of his powers, and how he deals with that mistake shows a lot about who he is.
The Competitor: Of course, occasionally you have that nemesis who is all about the competition, and that's it. He's not really a villain, and he may have nothing in common with the hero past he sees the hero as one of the greatest challenges of his career. Kraven the Hunter is the best example here: He sees Spider-man as a worthy foe, and therefore someone he needs to defeat. This is villain is different from the rest in that good and evil doesn't really apply to him; he can ally with the villains or hero, and it doesn't come off as forced. The character may even be a hero is his own right, he just likes messing with the hero as a sort of progress check on his own abilities.
Above all, remember to have some fun creating the Big Bad. It's a cliche, but your heroes are only as good as their villains, so make your villains as nasty as you possibly can. This is definitely an area you can have some fun with, so take full advantage of that. Do it wrong, and the villain fades into mists of memory; do it right, however, and you could have one of the most memorable characters ever!