In Wario Land II, Ball Bunny is one of the bosses in the game. He is a basketball player, and Wario must make three shots using him after he is transformed into a ball in a basketball hoop before Ball Bunny can do the same to him.
In Wario Land 3, Ball Bunny appears in appearance only. One of the kings of the Music Box world is transformed into Ball Bunny by Rudy the Clown, and fights Wario so he can't free Rudy the Clown, who Wario believes has been trapped by them. Instead of playing basketball, he now plays football (also known as "soccer" in America), and if he turns Wario into a ball and kicks him into the net three times, Wario loses the boss battle. However, if Wario jumps on Ball Bunny's head and makes a goal three times, being careful to get it above the tortoise's head, Ball Bunny will lose and the tortoise will help him get to the treasure.