not just a critical hit
a skill like power strike or mortal blow cancels out the attack
using power shot does it too
you first use power shot, start running away (they cant cast yet cause power shot's range is high) then until recharge time is up use power shot again....u automatically walk towards it and shoot the first chance u get, at the same time the stoney comes towards you and begins to shoot except YOUR shot gets off first and cancel's his out

then just kite him for the rest of his HP
