— Karate Duo Number 1
The Karate Duo Number 1 are two Zeus Guys (Bandit) in the Bowser's Kingdom show who sound and act like sterotypical Asians. They were even referred to as "A bunch of crazy asian sterotypes" by Lemmy Koopa. They are obsessed with a magical sweet known as Lucky Candy which gives them superpowers. The duo are voiced individually by Andrew Raskin and Patrick TeNyenhuis, who also voice Hal and Jeff respectively.
The Karate Duo Number 1 first appear in Episode 3, where they serve as minions of Bowser in the World 3 castle. They aid Lemmy Koopa in fending off Mario, but before they can do battle with him, Mario burns them both with fireballs (thanks to his Fire Flower power-up).
In Episode 5, Hal and Jeff go to the Karate Duo's house to get items that could bring back the dead (specifically, Princess Peach). The Karate Duo give them a special herb, saying that it will "breathe" new life into any dead person when planted. They also give them some Lucky Candy as a back-up if the herb doesn't work. As Hal goes to leave, Jeff quietly asks them if they have any ointment for a fungus growing on his "nether regions", to which the Karate Duo present him with more Lucky Candy.
In Episode 7, the Karate Duo appear at the beginning of the episode. While Hal and Jeff are watching television, the Karate Duo suddenly appear and say "Wii would like to play", before accidentally breaking the television whilst playing the Nintendo Wii. The Karate Duo claim they are not liable and disappear, but Hal notices that they left behind the Wii console. The Karate Duo reappear to take back the Wii before disappearing again.Episode 9, the Karate Duo appear as the main protagonists. They first appear at a campfire with Hal and Jeff, where they tell the pair a story of how they were searching for the "seven stars" under the commands of Smithy. As they go along, they encounter their old master, Frogfucious, who taught them to fight. At the end of the story, one of the two Karate Duo members dies, but Jeff interrupts the story and asks them how they are both sitting in front of him now. They respond with "LUCKY CANDY!"
In the Bowser's Kingdom movie, Jeff goes in search of the Karate Duo after Paul Hammerbro knocks him into a forest. After Jeff falls for Rick Finkelstein's trap, the Karate Duo appear and defeat Rick by knocking him off his cloud. The Karate Duo take Jeff in their car and drive onto a Mario Kart racetrack to escape from Paul Hammerbro, who is pursuing them. Later, Jeff and the Karate Duo arrive at a Ghost House and drive their car straight into Petey Piranha's open mouth. As Jeff is reunited with Hal, the Karate Duo eat Lucky Candy which gives them superpowers, allowing them to defeat all of Bowser's minions.