BB-K8, a droid from the BB-series of astromech droids, stood out with its black plating and served the First Order. On the hunt for Lieutenant Sol Rivas, this droid accompanied Captain Phasma along with TN-3465. During their time on Luprora, TN-3465 carried BB-K8 on their back for a portion of their assignment. Furthermore, the droid facilitated communication between TN-3465 and the Lupr'or. After Rivas was killed by Phasma, she also eliminated BB-K8 and TN-3465 to conceal her involvement in the destruction of Starkiller Base.
During the First Order-Resistance War, BB-K8 was stationed at Starkiller Base. During the Battle of Starkiller Base, BB-K8 was assigned to an auxiliary hangar. His role was to repair the TIE/sf space superiority fighter of TN-3465, a TIE fighter pilot. While BB-K8 was updating data, Captain Phasma arrived. She commandeered TN-3465's fighter for a mission to locate Lieutenant Sol Rivas. Phasma had falsely accused Rivas of weakening Starkiller Base's deflector shield to hide her own wrongdoing. The trio departed just before the Resistance attack destroyed Starkiller Base.
While pursuing Rivas through space in his TIE/fo space superiority fighter, Captain Phasma discovered that the laser cannons on their fighter were not working because BB-K8 had not finished repairing them. Out of frustration, Phasma kicked the droid. After Rivas' fighter ran out of fuel and landed on the isolated planet of Luprora, BB-K8 accompanied Phasma and TN-3465 to the planet. BB-K8 had difficulty navigating the rough terrain after they exited their TIE/sf fighter. Phasma then instructed FN-3465 to strap the droid to her backpack and carry it.
The group spent four days on Luprora searching for Rivas. BB-K8 accompanied Captain Phasma and TN-3465 as they waded through a lake after they spotted a nearby settlement. A tsw'ell attacked Phasma, but she managed to kill it. BB-K8 and his human superiors then went to a village inhabited by humanoid Lupr'or. There, Captain Phasma and TN-3465 learned that the R'ora, a fearsome native species, had captured Rivas and imprisoned him in their stronghold.
Later, Phasma and TN-3465, with the help of their local guides Dar'en and a Lupr'or girl, discovered an old Luprora starship equipped with technology, including jammers. After returning to the Lupr'or village, TN-3465 asked BB-K8 to translate her message into Lupre'en. However, the droid incorrectly translated "everyone" as "men." TN-3465 reprimanded BB-K8 for the error and instructed it to correct it. When BB-K8 protested in Binary, TN-3465 responded that she did not care if it made the droid appear foolish. Captain Phasma, who had put on her chromium armor, interrupted TN-3465, impressing the locals.
After Captain Phasma delivered an inspiring speech urging the Lupr'or to fight the R'ora, BB-K8 displayed holographic schematics of the R'ora stronghold. Under Phasma's command, the R'ora used electric generators to electrocute the Tsw'ells in the lake. The droid remained behind while Phasma, TN-3465, and the Lupr'or attacked the R'ora stronghold. Phasma succeeded in killing Rivas, but TN-3465 discovered that she was responsible for weakening Starkiller Base's shields.
After Rivas was killed, BB-K8 went back to their TIE/sf fighter. Phasma shot the droid with her blaster rifle, creating a hole in its round body and head, to conceal her secret and get rid of any potential witnesses. Phasma then murdered TN-3465, eliminating the second person who knew about her part in the destruction of Starkiller Base. Phasma created a false report claiming that BB-K8 and TN-3465 had died during the mission to kill Rivas for his supposed treason as she made her way back to the First Order fleet.
BB-K8 was a black BB unit designed to repair starships, including installing data updates. The droid had a single red photoreceptor and grappling lines for attaching to starship interiors during travel. BB-K8's round chassis made it difficult to navigate rocky terrain, but it had straps for carrying by a bipedal being. BB-K8 seemed capable of wading through water.
BB-K8, being an astromech droid, communicated in Binary but also understood Galactic Basic Standard and Lupre'en. However, he confused the Lupre'en words for "men" and "everyone," which annoyed TN-3465. The droid also showed a personality and felt embarrassed when TN-3465 told it to fix its mistake. Despite their strained working relationship, TN-3465 was shocked and appalled when Captain Phasma shot the droid to cover up her role in the destruction of Starkiller Base.
BB-K8's initial appearance was in Star Wars: Captain Phasma, a four-issue comic from 2017 published by Marvel Comics as part of the Journey to Star Wars: The Last Jedi promotional campaign. Kelly Thompson created it, Marco Checchetto illustrated it, and Andres Mossa colored it.