Arthur Turner (potrayed by Sterling Beaumon) is a former Wasabi Warrior and the son of Mr. Turner, the new owner of the mall. Because of this, he is a spoiled child, and is hated by the Wasabi Warriors. He shows most of his distaste towards Jack. Jack shows Arthur his hatred by throwing him into the wall.
In Dojo Day Afternoon, he calls the Wasabi Warriors "losers" and says they pretend to know karate, even though Arthur himself has no abilities in the art. At the end of the episode, he wanted to tear down the dojo, no matter what or who got in the way. In the end, his father grounded him for the very first time, Arthur not knowing what grounding is. Arthur is arguably the darkest character who opposed the Wasabi Warriors, wanting to tear down the dojo to win over them, even if that involved killing Jerry, Eddie, Jack, and Rudy. He has no idea what karate is considering he thought a green belt was higher than a black one. He probably will not make an appearance again.