Bart Simpsons leaves from Homer and Marge Simpson on a Skateboard. He walks around town to join Nelson Muntz at the playroom.
In the 1st fight we find the comic book seller (Jeff Albertson) played by Bart Simpsons and Willy the gardener played by Nelson Muntz.
In the 2nd fight we find Krusty the clown played by Bart Simpson and Willy the gardener played by Nelson Muntz.
For the last fight we find Mr Burns played by Bart Simpsons and Itchy the mouse played by Nelson Muntz.