We spar using NASKA rules and using core MMA rules. Sweeps, leg checks, head shots, etc. We fight realistically, because in the street, an attacker won't give a damn where they hit you as long as they take you out (pardon language). So we like to shoot and ground and pound as well as stand up and fight. Believe it or not, very few people get hurt (we wear helmets and gloves and stuff).