A modern derivation of Kung Fu found when a fight breaks out in the middle of the dance floor, mosh pit, or rave.
Usually involves the offending party being drunk or otherwise drugged and making an ass of themselves followed by an ass kicking under the bright flickering lights of the rave/dance floor which makes the whole thing look that much cooler.
Raver 1: "What the fuck happened?!"
Raver 2: "I dunno that fucktard pulled out a knife and the other guy went all Rave Fu on his ass!"
A Raver or dancer at a rave who knows martial arts and tries to pull it off as their dance.
Is that a new dance?
Nah thats just rave fu.