The Space Ghost parody universe became a bit smaller this morning as C. Martin Croker, voice actor behind classic characters Zorak and Moltar on Space Ghost Coast to Coast, Dr. Weird on Aqua Teen Hunger Force, and an animator in his own right died this morning from undisclosed causes. He was 54.

Born in Atlanta in 1962, Croker began working for the Turner Broadcasting System family of television networks in the early 1990s, animating several of TNT network’s “TNT Toons”. He would later help design and animate bumpers for Cartoon Network during the channel’s 1998 rebranding. During the same period, Croker paired his animation career with voice acting, working behind the scenes and portraying several characters on shows that would contribute to the earliest slate of programming on Cartoon Network’s Adult Swim programming block.

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Most famously, Croker voiced the characters Moltar and Zorak on Cartoon Network’s Space Ghost Coast To Coast, a surrealist reboot of the 1960s Hanna-Barbera cartoon Space Ghost that paired animation with live action guests. “Hosted” by the Space Ghost, the show saw the hero’s roster of enemies forced to serve as on-air sidekicks as punishment for their crimes. Croker’s portrayal of Zorak as a bitter, unrepentant supervillain who nonetheless discharges his duties as the show’s bandleader became one of the show’s most popular elements. Croker continued to voice the character on the even more surreal spinoff series Cartoon Planet and The Brak Show. He would continue to voice Zorak and Moltar along with other voices on Space Ghost-related productions through 2014.

Croker also voiced Dr. Weird and his assistant Steve on Adult Swim’s Aqua Teen Hunger Force, including the 2007 film based on the show. Other voice acting credits include the Cartoon Network series Sunday Pants and Perfect Hair Forever. As an animator, his work was seen on Comedy Central’s Ugly Americans, and of course Space Ghost Coast to Coast, where he served as animation director for 92 episodes.

Adult Swim made the news public early this morning, paying tribute to Croker on Twitter.