So, these are almost identical tasks to those on days 3 and 4, except you're profiling your antagonist instead of your protagonist. One of the most important things is to define who or what an antagonist is. And what do you do when your antagonist isn't a person??

If your antagonist is a person, then there a few things they should embody:
They should contrast your antagonist. If your protagonist (who is simply your main character) is good, then your protagonist is not so good (classic good vs evil). If your protagonist is bad, then your antagonist is the good guy. I know Rhonda's protagonist is the criminal, so in her case the antagonist would be the good cop who is trying to take the bad guy off the streets and prevent murders.
They should create obstacles for your protagonist. They should prevent the protagonist from moving forward towards their goals, or at the very least make it more difficult for them to move forward. They should create conflict.
They should not take over the story!

But what if your antagonist is not a person? Well, what else could they be?
They could be internal - an inner desire, fear or similar emotion that causes conflict in the protagonist. Consider Dr Jeckyll and Mr Hyde - they are one person who is both antagonist and protagonist, an extreme example of internal conflict.
They could be an environmental factor. Think of every natural disaster movie you've ever watched! Nature keeps throwing obstacles in the protagonist's way, forcing them to go around, go backwards or get creative. And they create danger and conflict that puts the reader on the edge of their seat.
It could be an animal - anyone seen Jaws?
It could be technology, such as Hal in 2001: A Space Odyssey or Skynet in the Terminator movies.
It could be societal - such things as racial or gender prejudices that the protagonist has to overcome or work their way around in order to achieve their goals.

So the same tools you used for your protagonist might not apply if the antagonist is not a person - but you need to write down as much detail as you can and get a good handle on as many aspects of your antagonist as possible, whatever it is. Write down its cause or motivating force. What drives the antagonist? What are the antagonist's strengths and weaknesses? How does the antagonist react to conflict or obstacles?

As always, feel free to discuss, agree or disagree. The more discussion, the better!

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