U.S. Army Sergeant Ralph Baducci was born in Brooklyn, New York, and eventually made his way to Denver, where he was trained in the martial arts with the Blind Master. He later moved to San Francisco and enrolled in the Arashikage Martial Arts Academy. He caught the eye of Storm Shadow, who then continued the training begun by the Blind Master.
Years later, Storm Shadow recruited Nunchuk for the G.I. Joe team's Ninja Force. On Ninja Force's first mission, Nunchuk and his teammates Dojo and Tj'bang fought Cobra Night Creepers in Beirut while helping Destro to avoid assassins hired by Cobra Commander. Continuing their protection of Destro, the Ninja Force and other Joes traveled to the Silent Castle in Trans-Carpathia, where they fought Cobra Vipers and a group of Red Ninjas.
It was the Ninja Force who discovered Firefly's connection to the Arashikage ninjas when the mercenary appeared in command of the Red Ninjas. The team later helped liberate the Cobra-controlled town of Millville from Cobra, fighting a band of Night Creepers. Shortly before the G.I. Joe team was shut down, Nunchuk and the Ninja Force opened up a martial arts training school on the site of the Soft Master's restaurant where Nunchuk's teammate Dojo had been trained many years before. The school was free to the underpriviledged young people living in the neighborhood. In the years after the Joe team was disbanded, helped Snake-Eyes train young Sean Collins (aka Kamakura) as a ninja apprentice.