Doom, a Clone Commander, served Jedi Generals Tiplee and Tiplar, her sister, during the Battle of Ringo Vinda in the Clone Wars. He fought alongside Anakin Skywalker and the 501st Legion. Doom and his unit battled Separatist droid forces led by Admiral Trench on the space station orbiting Ringo Vinda. In the thick of battle, clone trooper Tup of the 501st experienced a premature activation of Clone Protocol 66 due to his malfunctioning inhibitor chip, resulting in the murder of Jedi General Tiplar. Taking advantage of the chaos caused by Tup's actions, droid reinforcements pressured Doom and his troops to retreat while they investigated the general's death.
On the planet of Kamino, using the genetic material of human male bounty hunter Jango Fett, the clone trooper commander who would become known as Doom was cloned with the purpose of fighting and ultimately dying for the Galactic Republic as part of their massive clone army. This army first saw action when Republic Jedi engaged the droid forces of the Confederacy of Independent Systems on Geonosis, an event that marked the beginning of the intergalactic Clone Wars. Later, Doom was placed under the command of Jedi Generals Tiplar and Tiplee, her sister. The troopers under his command adopted a green color scheme for their armor, along with a yellow triangle as their unit symbol.
Doom, along with Tiplar and Tiplee, participated in a major campaign to seize a large space station controlled by Admiral Trench above Ringo Vinda, where Trench commanded his droid forces. The 501st Legion, led by Jedi General Anakin Skywalker, joined Doom's unit for this battle, which eventually reached a stalemate. During the intense fighting within the station, Doom's forces became greatly depleted. After several more encounters with Trench's droids, the Republic troops successfully secured a communications center. Skywalker then planned the next phase of the battle, ordering Tiplar and Doom to lead the remaining troops down one of two corridors leading to Trench's command post. Doom pointed out his limited number of men, leading Skywalker to assign ARC trooper Fives, clone trooper Tup, and ten other 501st troopers to assist Doom and Tiplar. Tiplee was to accompany Skywalker and the remainder of his troopers down the other corridor.
The Republic renewed their offensive, closing in on Trench's command center. Tiplar and Doom fought together, advancing with minimal losses. They eventually reached Trench's command center and joined Skywalker and Tiplee. However, as the battle raged, Tup, in a trance-like state, unexpectedly shot Tiplar in the back of the head. Doom witnessed the event but had to continue fighting due to the arrival of destroyer droids. Fives apprehended Tup, while Tiplee recovered Tiplar's body. Tiplar's death caused the attack to falter, and Skywalker ordered a retreat. The Republic forces regrouped in the captured command center, where Doom and his men mourned Tiplar. Tup's actions were the result of a Sith-implanted behavioral modification biochip within his head, a device that was secretly installed in all clone troopers. Tup's chip had malfunctioned, prematurely activating Clone Protocol 66, an order compelling clone troopers to execute all Jedi for treason.
Doom was created as a skilled fighter, completely loyal to the Galactic Republic, and was expected to follow orders without question. He understood the risks of his role and knew when to request reinforcements. He also recognized when retreat was necessary. Doom coordinated well with Master Tiplar, providing mutual support during combat. He and his fellow troopers mourned Tiplar's passing and expressed confusion over Tup's seemingly unprovoked act of murder.
Like all clones, Doom was a genetic copy of the bounty hunter Jango Fett, standing at 1.83 meters tall.
Doom wore Phase II clone trooper armor, complete with a kama around his waist, a visor, a flashlight, and an antenna on his helmet. By the time of the Battle of Ringo Vinda, his armor was heavily damaged from combat. The armor was primarily green, including the upper legs, chest plate, and most of the helmet. His vambraces, greaves, and boots were gray. The kama was green with yellow stripes, and both his helmet and chest plate displayed the yellow triangle emblem of his company. His left shoulder pad was also yellow.
In terms of weaponry, Doom preferred to use two identical blaster pistols to eliminate enemy forces. He used these handguns to great effect during the Ringo Vinda campaign.
Clone Commander Doom first appeared in previews for the sixth season of the TV series Star Wars: The Clone Wars. He appeared in the episode The Unknown, which premiered on Netflix in Germany on February 15, 2014, and later in the United States and Canada on March 7, 2014. Doom was not named in the episode itself, but his name was revealed in the episode's guide. Dee Bradley Baker provided the voice for Doom, as he did for all clone troopers in the series. Doom's design is inspired by the Marvel Comics villain Doctor Doom.
During the 2014 San Diego Comic Con, Hasbro revealed a new Clone Commander Doom action figure as part of the Star Wars: The Black Series toy line. The preview showed that the figure would include the two pistols he used in the TV show. The figure was released in 2015.