Slim was a clone trooper of the Galactic Republic. Early during the Clone Wars, Slim was on the planet Kamino, and got into a fight with the trooper Heater, who had previously deserted from the Grand Army of the Republic. Slim called Heater and the other deserters cowards, which angered Heater and caused him to punch Slim in the jaw and pin him against a pillar. As the other clones in the mess hall watched and cheered the fight, Slim kneed Heater in the gut and the two got into a grapple. The fight was then broken up by Clone Commander Wolffe, who wished to speak with Heater.
Slim first appeared in the fourth issue of Star Wars Adventures: The Clone Wars – Battle Tales, that was released on August 26, 2020.