I guess Jigglypuff can copy just as well as Kirby can if he feels up to it. Many of them do come with the Competitive ability, so this one was clearly up to the challenge. Imagine trying to play OoT or MM though. Every song just puts people to sleep. How is Jiggs suppose to save Hyrule if Epona keeps face planting into the middle of the field every time she is summoned? Walk? He ain't got no legs!