Get the replay (.rpl file) you want, open it with Notepad or another text editor. I'll use 0headkick.rpl as an example. The fourth line down, "FIGHT 0; headkick3 [MAD]hampa uke", says who participated in the fight. You could, if you wanted, change the line to "FIGHT 0; headkick3 cj2man [MAD]hampa". It's pretty simple, then just save the file afterwards and view it in Toribash.
hmmm how can i change uke's outfit that everybody can see. not only i can see but everyone who watches the replay like oblivion's?
How do I make my character have different colors or a custom head/body?
If you've played Toribash for a while, you might notice that people have customized characters. To do this, you must gain Toricredits and use them to buy stuff.
1) To get different joint colors and more, go to the Torishop and buy the items that you like.
2) To have a custom body or a head, you need to buy textures (click here). After you've done so, you can design your own texture on any art program and upload it as your texture.
Here is a tutorial on how to make and preview your own textures.