C-21 Highsinger was a droid bounty hunter that operated during the Clone Wars. He was part of a syndicate of bounty hunters that included Boba Fett, Latts Razzi, Dengar, Bossk, and Oked. Although a deadly combat droid, C-21 Highsinger had his battle programming pushed beyond its limits when defending Otua Blank's subtram from the swift Kage Warriors.
- Star Wars: The Clone Wars – "Bounty" (First appearance)
- Dark Disciple
- Star Wars: Darth Vader 16: The Shu-torun War, Part I