Two Ball Game
This happened earlier today.
Get a wiffle ball and a soccer ball. Divide approximately 12 people into two teams. At any moment, one is offense and the other is defense. One of the players (the "goalie") on the defensive team guards themselves with a wiffle ball bat inside an equilateral triangle approximately 12 feet on each side. The offensive team is trying to throw the wiffle ball at the goalie. The defensive team is trying to kick the soccer ball at the player in possession of the wiffle ball.
Points are scored when the offense hits the goalie with the wiffle ball (throwing underhand from outside the triangle), or the defense hits the offensive player in possession of the wiffle ball with the soccer ball. Because the latter is a bit more difficult than the former, it might be assigned more points (but we never got that far). When a point is scored, the player it was scored by/against becomes the goalie. The former goalie throws in the wiffle ball.
Additionally: it might make more sense if both balls may be either kicked or thrown. It might also be easiest to play this in a court, where the soccer ball cannot be lost when it misses a target (or with multiple soccer balls).