The black balls are bludgers and the red ball is the quaffle. If a bludger hits you the game ends. You get 10 points every time you touch the quaffle and you win when you get 1000 points. I might add a snitch and goalposts later.
CREDITS Scratch J.K. Rowling for quidditch bludgers quaffles the color green the color blue the color red the color black the color brown