HK-51 series assassin droid

"Manifesto: The Maker created me for the sole function of deleting high-ranking organic troublemakers of the galaxy. These deletions must be conspicuous and provide an object lesson to other organic troublemakers. All other mission parameters are secondary."

- HK-51

HK-51 assassin droids were advanced versions of HK-50 assassin droids. They were acquired by the reconstituted Sith Empire around a decade into the Cold War. An Imperial freighter containing the droids had crashed on Belsavis some time later. Around 3,640 BBY, renegade Sith rediscovered the freighter.

Characteristics
"Schematics for HK generation 51: Blaster to accuracy ratio: increased by 21%. Durasteel impact frame resistance: increased. Conclusion: halting production. Units are in standby mode, pending further testing of behavior cores and assassination protocols."

- Log of the HK-51's development status

Behind the scenes
"Revelation: We have already begun construction on a new generation of HK units. When the last of our deficiencies are accounted for and corrected, they shall be the most formidable assassination droids in the galaxy."

- An HK-50 assassination droid

In a removed part of Star Wars: Knights of the Old Republic II: The Sith Lords, HK-47 would confront G0-T0 on Malachor V, and a group of HK-51 droids would come and help him defeat G0-T0, if HK-47 had programmed them to aid him while in the HK Manufacturing Plant (HK-47 could also choose to destroy them, causing him to lose to G0-T0). The HK Manufacturing Plant was also a removed part of the game.

HK-51 droids later made an appearance in the 2011 video game Star Wars: The Old Republic. At level 50, a small quest chain in the "Section X" area of Belsavis leads to the discovery of the crashed Imperial battlecruiser Fatality, carrying a full compliment of damaged but salvagable HK-51s. To claim the HK-51 for themselves, the player must first team up with others to explore the abandoned Czerka Corporation cruiser Theoretika in the Unknown Regions, and obtain a set of HK schematics. Afterwards, they must collect certain HK parts from Coruscant, Dromund Kaas, Taris, Hoth and Tatooine, from the False Emperor flashpoint on normal or hard difficulty, and either the Maelstrom Prison (Republic) or the Foundry (Empire) on hard mode. The part on the capital worlds (Coruscant and Dromund Kaas) requires a character of the opposite faction (i.e. making a Republic character to obtain the part on Coruscant for an Imperial "main") of at least level 10, the level around which players normally leave their starter world. After the parts are collected, the player returns to the Fatality wreck on Belsavis, and confronts a Sith of the Dread Guard called "the Lord of Agony", again with a group. After the Lord of Agony is defeated, the player may claim their HK-51.

Appearances

 * Star Wars: Knights of the Old Republic II: The Sith Lords
 * HK-51 Revealed
 * Star Wars: The Old Republic