Sometimes a very difficult character to develop, but a strong antagonist is as important as the protagonist. There are several different forms of antagonists, a societal antagonist, a particular person opposing the protagonist, or maybe the person opposing the protagonist is himself or herself. It is possible to flesh out the relationship more, but at the basic level this is the description of the connection between the protagonist and the antagonist. But the development of the Antagonist is what enhances the relationship between the two characters.
But what makes a strong antagonist? What drives the antagonist to carry out the plot against the protagonist directly or indirectly? I believe that developing a strong antagonist requires the same amount of thought and inspiration as it does to create a strong protagonist. A question every author should ask themselves, whenever they write a story that revolves around two characters is
“What drives these people?”
What drives a protagonist to go on this adventure or quest to fix or do what he believes is right? What about the antagonist? Is it not possible that the antagonist could be on his or her own adventure or quest to do what they believe is right? Sometimes the antagonist could be fairly straight forward and still provide a strong narrative.
Voldemort in Harry Potter wanted power
The Agent in Serenity wanted to kill River
While the objectives were fairly simple, the backstory of these villains that led to these objectives were not.
Voldemort grew up alone with a lust for power and a fear of death, hence the Horcruxes and the Deathly Hollows. The more power Voldemort gained, the further he believed he was from death. While reading the books we learn more about his past, his parentage, and his ambitions
The Agent in Serenity was essentially programmed to believe that the organization he works for is benevolent and flawless. In one part of the movie he even acknowledges that he himself is an abomination in the world his masters had envisioned. But towards the end his eyes are opened to what the Alliance really is and suddenly everything changes.
The antagonist is a complicated character. They may just be following orders, doing what they believe is right, or forced to do what they have to. The idea that an antagonist is a villain just for the purpose of being evil is, in my opinion, very weak when there is so much more potential for that character. If you look at Saren from Bioware’s Mass Effect, he is a very interesting antagonist. At first it seems as though he’s a villain out to commit genocide against humanity. However, though he does have prejudices against humanity, we find that he is a pawn of a far greater evil and what he does he does to try and preserve life in the galaxy. As the player, we discover that what he does he does out of fear, an emotion that is very understandable and makes a character more personable. Its a good example of creating an antagonist that is more than just a villain for the sake of filling that role within a story.
I hope this helps. There are several other stories that might work as better examples for the arguments I’ve made, but these are some stories that I experienced growing up and have influenced my own writing to a great extent.