‘You can run THAT fast?’ you reciprocate

He looks humbled at your reply.  You test his guard with a dashing feign, it looks as he does indeed have a weak spot.

With a flourish of steel he says ‘I got this scar on my face during a mighty struggle!’

Do you

Reply ‘I hope now you've learned to stop picking your nose!’ and strike for the weak spot

Reply ‘Behind you a GIANT three headed monkey!’ and strike for the weak spot