Have you ever heard of this before? Advice?

Has anyone heard about this/does your school do this? I'm a freshmen at college so this is my first formal but apparently there is a gunge/slime tank and if you participate in games and lose, you get covered in slime/gunge. It's a formal though so I'm going to be wearing a really nice black evening dress and heels. Should I stay out of the games, although it won't be as fun, or participate and take a chance of getting messy?