A very intense game of water and/or beer pong where if the ball completely misses the table or cups, the opposing team can grab the ball before it hits the ground and fling it at the people that were tossing. If you catch the ball, you must yell "BOCA" and aim for the opponent's faces. If you hit them in the face, you get a cup.
Man, that was an intense game of Boca last night. I still have the marks on my face to prove it!!