At the count of three both should start blowing into the tube for as long as they can. After 10 seconds or so, someone will need to take a breath and will get egg all over his face. This inexpensive stunt will have the rest of the group laughing and grossed out at the same time. Take two old, but clean, knee-high gym socks and stuff each sock with another sock. The contestants must remain within these boundaries during the game.
Gladiators compete by swinging their war socks at one another, each trying to land the first blow.
For safety, provide goggles for the players. A referee decides who struck first. Tournament play works well, with the winner moving on to fight again. Or you could play best of three rounds. Now write some Bible verses on plain white paper and make as many copies of those sheets as you have teams.