Butch Crichton was an alias assumed by John Crichton during his first visit to Dam-Ba-Da. After encountering Rorf and Rorg, who were searching for Moya's crew, Crichton pretended to be a bounty hunter seeking the same prize. Crichton maintained this act, even when the two had captured Ka D'Argo. It was then that Butch revealed he had taken another, higher offer and freed D'Argo instead.
Even after the Vorcarions had left, they still believed that they had been dealing with Butch, the Sebacean bounty hunter, rather than the human they had sought all along.
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Butch Crichton appears in one episode of Farscape.