Enable War Mode and slay 1 Horde Player within the world.
The b-b-barber shop? I'm sorry, what? You want to know where the barber shop is? I'm sorry <race>, do you know there is a W-A-R going on right now? Speaking of which, what have you done for the Alliance lately? Get out there and slay some Horde, or I'll shave your head myself.