HK-54 was a droid of the HK series. It was build thanks to a Black Sun member who discovered the aged HK-Factory on Telos. With the schematics of the HK-51 model, the Black Sun was able to create a better, more accurate, and more deadly model. This was the birth of HK-54. The droid was not aware that there was still another HK-unit around in the galaxy: HK-47. While on Mustafar the two eventually had an ultimate confrontation, HK-47 convinced HK-54 to fight in his droid army. When the droid army was defeated HK-47 and HK-54 where the only survivors.