This is a low-budget filler episode. Fans and reviewers often note it looks "rough" or "off-model," likely to save resources for the upcoming Royal Knights tournament arc.
When their food stalls fail to attract customers, they resort to childish games (arm wrestling, thumb wars) before deciding to settle things with a "death match". Black Clover (TV) (Dub) Episode 68
The English cast shines here. Christopher Sabat (Yami) and Justin Cook (Jack) have fantastic chemistry, leaning into the over-the-top screaming and petty insults that make the rivalry work. This is a low-budget filler episode