Approximately one year after the First Battle of Geonosis, Roshton was assigned to accompany one of Supreme Chancellor Palpatine's advisors, Kinman Doriana, to Cartao. Their mission was to secure the assistance of Spaarti Creations for the manufacture of modern Spaarti cloning cylinders. The Separatists soon discovered the plan and launched an attack on Cartao.
Roshton had been given orders to defend Spaarti Creations from being captured and to ensure the continued production of the Spaarti cloning cylinder, but he soon realized that the two orders contradicted each other. If his troops engaged the enemy, the manufacturing facility would probably be damaged, but if they didn't fight, the facility would easily be captured by the Separatists. He commanded only nine hundred clone troopers, while the Separatists had five thousand battle droids and their accompanying MTT large-transport vehicles, AAT battle tanks, and hundreds of STAPs.
Despite the damage the fire-fight might cause, Roshton decided to have his troops hide inside the facility for cover. After meeting Jafer Torles, Cartao's Jedi Guardian, Roshton decided he needed a new strategy that would prevent serious damage to the facility. He ordered his troops to move into the tunnels that led away from the main plant and establish positions from which they could harass the rear flanks of the Separatist forces across the neighboring city and forest area.
Roshton, in the guise of a landscaper, planted remote-activated landmines around the grounds. His plans were going well until Separatist forces collapsed the exits to an access tunnel, trapping his troops within. While Kinman Doriana, Jafer Torles and Republic Lieutenant Laytron launched a daring rescue mission which freed Roshton and his remaining troopers, a Republic gunship destroyed the entire facility, supposedly under the orders of Jedi Knights.
- Hero of Cartao (First appearance)