This article examines media participation through affective political economy, using as a case study the documentary Knuckle, a profile of Irish Traveller fighting. The film incorporates videos recorded by fighters and their families. Boasts and threats from one clan to another expand in circulation and become increasingly monetized as they are repackaged. Combing media political economy with Sarah Ahmed’s concept of affective economies, this article explores how, through such circulation, the videos help accomplish the affective work of world building, not only within Traveller society but also beyond it in realms such as mixed martial arts (MMA).