Part one: Creating a villain in general
Don’t create a paper cut out of evil. Unless you’re writing a story for little kids, give your villain depth (think of the good witch and the wicked witch, a protagonist would be closer to the good witch, while the antagonist should be closer to the wicked witch, but they should never be just the good witch or just the bad witch), just like you would any character. There is no such thing as pure evil.
Give your villain a good motive. If somebody hurt them, then they may want to hurt that person, their relatives, or the entire world. They may also be doing it out of greed. Whatever it is, it’s up to you.
Forget the whole “Good deep down” thing. People aren’t like cupcakes of evil with a center of frosting of good. Good and bad a jumbled together. A man who kills enemy soldiers by the thousands, may run an animal shelter out of pure love for animals. Or a hateful dictator who rules wi