The Best Offence was developed in the army in 2006 when a skinny half-asian private saw a colonel and said "If he tries to come over here I'm going to throw my Kevlar at him and knock him down and shit in his mouth."
The Best Offense has the twofold effect of both rendering the target prone as well as infecting him with a clinical condition called
Shitmouth, which can lead to the gum disease gingivitis as well as
assbreath.
The best offense does not require you to use a Kevlar helmet to knock the target prone, but traditionalists of the practice still use one.