This isn't too tough if you make sure to purchase Unlimited Hakumen from the gallery. It would be a bit tougher against an AI, though it would still be possible. That said, it's best in local versus against a second controller.
When the match begins, drain the barrier gauge by holding away + R2. Once it says "Danger", activate Overdrive with Hakumen. Then, use his distortion (Half-Circle away, Forward + C or
on default controls) and hold it until it automatically activates. Follow this up with a Half-Circle forward + C and then another
. It should do just over 10,000 damage.