Like his cousin Stitch, Sparky is shown to be highly mischievous. He is very hyperactive and fun-loving. He also shares Stitch's habit of picking his nose with his tongue. Sparky was once a very bad and mischievous creature—as he was programmed into his very being by the alien mad scientist Jumba Jookiba. His original purpose was to cause massive electrical surges which would disorientate those that were caught in it, but he changed when he was caught and reformed shortly after his activation.