Goomba is a fucking Goomba.
In all seriousness, he's a generic enemy in Super Mario Bros. series. Specifically, the Goomba that appears in EDBW is based on the film version of Super Mario Bros. He is a former Hardcore Champion, the winner of the prestigious Woody Memorial Battle Royale, and a survivor of "The Purge." Goomba teamed with Charles Barkley as The Monstars until retiring early in Season 6.