I found this cool article at
www.howstuffworks.com about all the different enemies Superman could fight and if they had a chance of beating him.
Take the Jedi for example...Do you think a Jedi Knight could take Superman?
How about a Sith Lord?
Or maybe Gandalf from Lord of the Rings?
All of those types of characters and more can be found in that cool article.
Check it out hereWhat do you think?
Are there any enemies that weren't mentioned that you think might be able to beat him?