The first that comes to mind is Satan from Milton’s Paradise Lost. You can call him an antihero of sorts, but he’s more than that. He’s the biggest bad guy of all time. He might be the protagonist, but he also might be the villain. He is clever, a master-manipulator, incredibly reasonable, and persuasive in his point of view. He’s the bad guy we almost want to side with. But, remember, he’s Satan, quite literally.
When I think of a compelling bad guy, there’s a reason why Satan of Paradise Lost is the first character called to mind. He’s a rational character, but he’s also emotional. He’s conflicted even in what he wants. To top it off, he’s a great speaker – easily one of the greatest speakers in all of English literature. He speeches at times will make him out to be a victim of his situation and become so logical that you might even feel momentarily swayed. But, don’t let that fool you, he’s still evil. He’s still Satan. He knows how to twist our view of his situation to draw out sympathy. We start with him chained to a burning lake in Hell. He is a character who wants you to feel sorry for him. He’s always posing as sympathetic, but that’s not the whole conflict.
Okay, let’s move on to the practical. While Satan from Paradise Lost is a great example, let’s go deeper. What is going to make a villain compelling?
You don’t actually need to have a first person account from your villain for us to get where they’re coming from. A compelling villain is going to have their own perspective on their situation. They believe they’re in the right, so it’s their job to show their side of the story. In the Harry Potter series, we get enough of Voldemort’s point of view to understand what he wants and what led to him making the choices he makes.
Know the Stakes
Just like in writing your protagonist, you’ve got to know, what does your villain have to lose? What will happen if he’s unable to achieve his goals? This will not only heighten tension, but help readers understand his motivations. Additionally, if your villain is guilty of doing something terribly immoral, what in his mind is the end that justifies the means?