Joe Agate

From Peanuts Wiki

Joe Agate is the expert marbles player and bully in the TV special He's a Bully, Charlie Brown.He is very mean and cruelly cheated Rerun out of his marbles but Charlie Brown got Rerun's marbles back. His first appearance was on April 7 1995

he also appeared in the comic strip when he won Reruns marbles (like in the TV special) and Charlie Brown won them back