Can't you do the same to him?

I had this guy at work giving serious nasty stares. At first I thought this guy must be well connected and I'd better tread lightly.

The absolutely nasty look continued for about two weeks and it was really affecting me.

I'd describe it as the type of state two guys do before a fight.

I started asking around and after talking to about seven or eight people from various departments over the course of a week was convinced he couldn't be a political threat to me and wasn't aligned or protected by any of the managers.

I was connected and would have had some protection.

I was stronger physically so decided to confront him.

Next day at the coffee machine, I walked to him and said, how goes it B1tcth ?

He completely went passive and said, good, good, good.

A few weeks later he needed a gentle reminder and after that always had a smile for me.

Not sure if a response like this is appropriate or even allowed here and in that case I'll delete it.

Sometimes bullies just need a little push back.