An unknown adversary in a dream often represents a part of yourself that you do not want to accept or face, or a memory that you want to keep hidden from yourself.
Sometimes, the same adversary will appear repeatedly in you dreams. This can be a sign that you need to face this troubling aspect of yourself or this difficult memory.
The next time you encounter your adversary in a dream, instead of fighting them, see if you can calmly approach them and ask them what they want.
If the adversary in your dream is someone you know in waking life, your dream adversary can represent something that you are conflicted about in waking life.
For example, if you dream that your adversary is a parent or your boss, you could have trouble accepting authority.
Fighting an adversary in a dream can be a way for your unconscious to release repressed anger.
Dreaming of an adversary can mean that you are worried about a threat in your life. Your unconscious is telling you to prepare for danger.