Luke Skywalker was a character that appeared in 3 episodes Sonic For Hire: The War: Part One, Sonic For Hire: The War: Part Two, and Sonic For Hire: Star Wars.  

Luke first appeared in the "War" arc as part of Darth Vader's team in "Family Feud"; he never spoke, but Darth Vader declared him to be a "constant disappointment." He later appeared in season 5, where Sonic and Co. found him bored to death with life on Tatooine... literally. He begged Sonic to kill him, but it was eventually the near-terminally dehydrated Earthworm Jim who ultimately killed him in a bid to escape the arid planet.