Batman: The Animated SeriesIn Batman the Animated Series, the Condiment King was a stand up comedian named Buddy Standler, who judged an annual stand-up comedy competition. He and his fellow judges rejected a comedian named Shecky Rimshot, who was really the Joker using an alias. As revenge, Joker used the Mad Hatter's mind control devices to turn them into supervillains. Buddy used ketchup and mustard sprayers to hold up a popular restaurant. Buddy was quickly defeated by Batman, but was hospitalized in the process. It was later revealed that the Condiment King, along with the other "villains" were brainwashed by the Joker, which resulted in him and the other two free of all criminal charges.
Comic Book History
This Condiment King's real name was Mitchell Mayo, an obvious pun on mayonaise. He was defeated repeatedly by Batgirl, Robin, Black Canary, and Blue Beetle. Like the television version he was very weak and was more or less a comic relief character. He eventually became one of the many loser villains who joined General Immortus' army. He along with several villains got power upgrades. His ketchup and mustard sprayers now shot corrosive acids. He is killed however by his team mate Human Flame by being choked to death with a ketchup bottle.
The LEGO Batman Movie
The Condiment King appears as an ally of the Joker in the 2017 LEGO Batman Movie. After Joker reveals that the Condiment King is one of his allies, he assures that this person is real and "might be worth to google".