This ability can be upgraded to be able to stun all enemies within a certain distance in the direction faced currently. When upgraded, the size and strength of the stun distance depends on the current Hit Counter (weak at 0x-14x, stronger at 15x-29x, and strongest at 30x hit counter and up).
Once the target has been stunned, attacking it will result in a rapid flurry of blade thrusts that does low damage for each individual strikes, but attacks very quickly and ends with a lethal finisher.
Note: The Blade Flurry, when attacking a stunned target, benefits from Critical Strikes, where presses should be timed accordingly. This allows very high hit streaks to be built up extremely rapidly, which can be used to provide numerous other combat benefits.
Wraith Stun does not work, however, on Captains or Warchiefs with the "Wraith Stun Block" Strength, as they will block your Wraith Stun attacks from the front.