In the game he will first be seen as a regular Goomba who somehow turns into a giant Goomba. He would try to ram into Mario. Mario can avoid Mega Goomba's attacks by crouching into a small gap or jumping onto a ! Switch to make two rising platforms appear so Mario can rise up and Ground Pound on Mega Goomba three times before it passes out. After defeating Mega Goomba, Mario will gain the key to World 5.