Just like any other Blood Sport or Death Race, this contest is played by the protagonists against a team of competition fielding a diverse array of Dog Skull and Motor Vehicle.
It is a form of Jousting, that does not include being chained or tied to a rock with a sword made of Feathers or Seashells.
Instead it uses "Fluid Dynamics" the ball's volume has been partially filled with a Colloidal Heavy Metal, such as Gallium-Mercury. As such, the ball displays a chaotic vector of motion similar to a Double Pendulum or Strange Attractor such as a Double Scroll.
If you win, you win Butterflies! Yay.
However, David Carradine, Sylvester Stallone, James Caan and Jimmy Smits are on the opposing team.
https://www.powerthesaurus.org/fluid_dynamics/synonyms
Do you feel sporty? Punk? We'll do ya?