Sack War is when you take 2 grown men from Mongolia and then you have them smash each others sacks in till they break or 1 gives up.. then the loser gets his sack licked till he jizzes.
Tengis: i sack war champion you will never defeat me.. You wish to challenge me?
Black Man: Bring it Nigga you aint got shit you sack tiny nigga.
It is when one man tries to break the other man's balls/ ballsack with his own. This is achieved by thrusting the sack at eachother for impact, this violent bloodsport was made famous by the world champion Tengis hailing from Mongolia.
Bob:"Dude that guy over there beat me in sack war."
Bob:"You dont wanna know."