I’m flat out writing (and sadly, doing some re writing) of my novel. It’s actually getting there, and as long as I keep my nose to the stone I’m going to make 50,000 words by the end of the month. The reason for the big rewrite (almost 10,000 words need to be changed) was a fundamental problem I had with my main character (s).
I had no idea what they wanted.
Of course the good guys wanted life, liberty and happiness and the bad guys wanted money and power and all the moustache they could twirl but as to actual goals beyond surviving (and killing each other) I had no idea.
I’m a seat of the pants writer by nature, and planning comes difficult for me, but figuring out what your character wants is a nice, easy, non restrictive way to set some important things up before you get halfway through your story and have no idea where it’s going.
Even if you don’t yet know your plot, you can ask yourself what your protagonist wants from the next week of their lives. In the case of my main character one of the things he wants to do is stop working for his brother. Despite the more outlandish parts of my upcoming book, that desire is going to drive him towards certain decisions in the book. Another fundamental desire of his is towards protecting the people he loves, that too is going to change the way he reacts when things get ugly.
Try the same trick with your antagonist. I can’t quite go into my main bad guys psyche without giving everything away before I’ve written it, but if you look at any of your favourite books (I recommend Neil Gaiman for excellent antagonists that actually have some depth) you will be able to boil the bad guys motivations back to one of a very few things. Are the bad guy’s motivations selfish? If they are that’s the most common motivation for a bad guy to have, and there’s nothing wrong with that. If they want millions of dollars and your protagonist happens to be in the way of that, their reaction to being thwarted is what’s going to turn them from frustrated everyman into a true nemesis for your main character. Bear in mind that a bad guys* motivation can also be altruistic, but their pursuit of those altruistic goals can be what makes them the antagonist. A good example would be the environmental activist that decides that murdering timber cutters is a good plan. Most people can sympathise with the goal of cutting back on logging, but killing people to achieve it is beyond a rational response.
If you can combine the two into an antagonist that has their own selfish desire mixed in with an altruistic motive, then that’s the best thing you can do for your bad guy. If they think they’re actually a hero, then that’s even better. When was the last time you met someone acting like a real jerk that knew they were acting like a real jerk? I’m sure they’re out there, but for the most part people acting like jerks think they’re in the right, and the people they’re in conflict with are the ones being unreasonable. Of course to make your book interesting, your antagonist needs to go beyond ‘jerk’ into ‘nemesis’ or possibly ‘diabolical madman’ depending on your story. It’s the same concept though, just on a larger scale.
This has been a long post already and I desperately need sleep. Ponder what your characters want, with and without your main plot points driving them. Then, especially for your antagonist (s), consider how they justify those goals to themselves.
* I feel the need to point out that when I say good guys and bad guys, I actually mean good/bad guys/girls/squid creatures of your choice.