K2-B4 functioned as second-in-command to Commandant Osi Sobeck, a Phindian who oversaw the Citadel prison belonging to the Confederacy of Independent Systems on the planet Lola Sayu, during the Clone Wars era. This T-series military strategic analysis and tactics droid was active in 20 BBY. Following a rescue attempt by the Galactic Republic to free the prisoners, K2-B4 played a role in implementing the security protocols of the facility. He supervised operations from the central command before embarking on a personal search for the intruders.
K2-B4 would eventually discover the stolen supply shuttle utilized by the infiltration team to gain access to the facility. However, he was deceived by a squad of reprogrammed battle droids fighting for the Republic. As the prisoners successfully escaped the facility and fled across the desolate terrain of Lola Sayu, K2-B4 commanded a Separatist defense fleet that established a blockade around the planet. Nevertheless, the droid was ultimately unable to prevent a Republic fleet from penetrating the blockade and extracting the escapees.
During the Clone Wars, K2-B4, a T-series military strategic analysis and tactics droid manufactured by Baktoid Armor Workshop, served the Confederacy of Independent Systems in their conflict against the Galactic Republic. In 20 BBY, the droid was stationed at the Citadel, a prison located on the planet Lola Sayu. In this capacity, he aided the Citadel's commander, the Phindian Osi Sobeck, in guarding Republic prisoners. These prisoners included prominent figures such as Jedi Master Even Piell, Captain Wilhuff Tarkin, and various clone officers, all of whom were subjected to torture in an attempt to extract information regarding the Nexus Route. This hyperspace route was crucial for infiltrating both Republic and Separatist space.
Shortly after the arrival of the prisoners at Lola Sayu, K2-B4, operating from Central Command, scanned an incoming supply shuttle. After confirming the absence of life forms on board, K2-B4 authorized the pilots to proceed, instructing them to maintain their designated course. However, unbeknownst to K2-B4, the shuttle was actually carrying a Republic rescue team dispatched on a mission to liberate the prisoners. The team had successfully bypassed the life-form scanners by being frozen in carbonite. When the supply ship deviated from its intended course and failed to arrive at its destination, K2-B4 promptly notified Sobeck. Soon after, Sobeck was alerted to the presence of the infiltrators when they triggered a security mine. The commandant then summoned his elite unit, a squad of commando droids, and K2-B4 informed him upon their arrival at the command center. Sobeck dispatched the droids to confront the intruders, but they were ultimately unsuccessful.
The Republic rescue team was eventually successful in freeing the prisoners. During the attempts to thwart their efforts, K2-B4 informed Sobeck that Count Dooku, the Separatist leader, was awaiting communication via hologram. Dooku was displeased with Sobeck's progress report regarding the recapture of the escaped prisoners. Subsequently, the Phindian instructed K2-B4 to refrain from surprising him with transmissions from the count in the future. Shortly thereafter, K2-B4 located the missing supply shuttle and also discovered a squad of B1-series battle droids along with the astromech droid R2-D2. K2-B4 identified R2-D2 as a Republic intruder. The tactical droid then ordered the squad of battle droids to escort R2-D2 to the interrogation center, unaware that the droids had been reprogrammed and were now serving the Republic. Upon the droids' escape, K2-B4 issued an alert calling for their capture.
As the Republic prisoners successfully exited the facility and continued to evade capture, traversing the desolate landscape of Lola Sayu towards a designated extraction point, K2-B4 was placed in command of the Separatist defense fleet that was blockading Lola Sayu, which Sobeck had ordered to be reinforced. From his position aboard a Lucrehulk-class Battleship, the droid was tasked with ensuring that no ships breached the blockade and was instructed to contact Sobeck upon the arrival of reinforcements. However, when a Republic fleet arrived, K2-B4 was unable to prevent them from entering the planet's [atmosphere](/article/atmosphere]. Consequently, the Republic forces successfully extracted the remaining members of the rescue team, including those who possessed knowledge of the Nexus Route, and returned to the Republic capital of Coruscant.
K2-B4 made his debut appearance in "The Citadel," which was the eighteenth episode of the third season of the animated television series Star Wars: The Clone Wars. Ashley Eckstein, who also voiced the Jedi Padawan Ahsoka Tano in the series, provided the voice for the character, as credited in the episode. The episode was initially broadcast on February 18, 2011.
The production team named K2-B4 in honor of the renowned basketball player Kobe Bryant, as several members were avid supporters of Bryant's team, the Los Angeles Lakers. Bryant wore the number 24 jersey during the later years of his career, and the name K2-B4 was derived from Bryant's number and initials. The droid's color scheme is not only reflective of Lola Sayu's environment but also of the Lakers' colors. Michael Buffington Jr. created the initial concept art for K2-B4, dating back to January 29, 2010. Later that year, the model for K2-B4 was finalized for the episode around the same time that Bryant and the Lakers secured the NBA Championship.