Sparky (AKA: Experiment 221) is a genetically engineered exterrestrial alien experiment. He is voiced by Frank Welker
Sparky resembles a yellow chinese dragon/monkey/lightning bolt shaped creature with a small body, large oval-shaped head, a pair of long protruding antennas, two blue eyes, a wide mouth, a wiry tail, a pair of triangular ears, two short arms, and two stubby legs. His body can also transform into a streak of electricity, allowing 221 to travel through electrical-powered machines and short circuit them.
Sparky's main function is electrokinesis. He can create massive crippling power surges, shoot lightning blasts from his antennas, and release a massive discharge of electrical energy. Sparky can also travel through electric-powered appliances and machines, short-circuiting them in the process.
Sparky first appeared in Stitch! The Movie. He was first activated by both Lilo and Stitch when they need to recharge Jumba's ship in order to rescue Jumba from Gantu. However, Sparky escaped Lilo's house, rampaged throughout Kauai, and short-circuited some portions of the entire Hawaiian town. But, Lilo and Stitch successfully captured Sparky at the local hotel. Sparky also made a stowaway in Gantu's ship, rescuing Stitch and Lilo after creating a power surge on Gantu's ship and making an escape in Dr. Hamsterveil's ship. Finally, at the near end of the movie, Lilo decided that the abandoned lighthouse would make a great home for Sparky.
Sparky also appeared in some episodes of Lilo & Stitch: The Series, as well in the PSP game of Kingdom Hearts: Birth by Sleep as a boss character for Terra's story mode.