Colt served within the Grand Army of the Republic during the Clone Wars as a Clone ARC Commander. He held the position of commanding officer for the Rancor Battalion, working alongside commanders Havoc and Blitz. During the Battle of Kamino, he met his end at the hands of Asajj Ventress.
Like all clones, Colt was a genetic duplicate of the famous bounty hunter, Jango Fett. His training took place on the aquatic world of Kamino. Sometime during the Clone Wars, he achieved the rank of Clone ARC Commander and took command of the Rancor Battalion.
Leading up to the Battle of Kamino, Colt, together with bounty hunters Bric and El-Les, supervised the instruction of clone cadets. He chose Bravo Squad to be the first to undertake the final challenge because the squad's cadets had accomplished their practice run in record Time, or "ARC trooper time," according to Colt. From an elevated observation point overlooking the training area, the commander directed El-Les to start version THX, variable 1138, of the Citadel Challenge. He was highly impressed by Bravo Squad's performance in the test and praised the instructors for their training of the cadets.
Domino Squad was next, and Colt instructed El-Les and Bric to increase the difficulty of the Citadel for them. As he watched their combat, he quickly became disappointed with Domino Squad's "sloppy" and "unorthodox" performance. After Domino Squad broke formation, disobeyed orders, and violated rule number one by leaving an injured CT-00-2010 behind, Colt halted the test. Consequently, El-Les had no choice but to automatically fail Domino Squad. However, the squad later succeeded after being granted a second chance to pass the simulation. Following Domino Squad's graduation, Colt and his fellow ARC troopers bid farewell to the cadets as they were deployed as soldiers for the Republic.
Colt and his fellow ARC troopers stayed on Kamino. When General Grievous, who led the droid army, and assassin Asajj Ventress unexpectedly attacked Kamino, Colt was tasked with defending Tipoca City. There, he encountered Grievous and, with the help of a small squad of clone troopers, managed to hold his own against him. However, he soon faced Ventress, who used the Force choke on him. The impact of being slammed against the wall caused his helmet to fall off. Ventress then proceeded to kill him by impaling him with her lightsabers, while simultaneously kissing him on the cheek. After deactivating her lightsaber, Colt's lifeless body fell to the floor.
A digital card featuring an image of Clone ARC Commander Colt was released on Star Wars: Card Trader on October 12, 2018. However, the card's title incorrectly identified him as "Clone ARC Commander Hammer." "Hammer" was the name used in production for another ARC trooper.