I'm going to call my ex-best friend a dick.
Why would you do that? What did he do to you?
He's always telling me that I'm paying too much attention to work.
Just ignore him, it probably upsets him that you are so focused on your career. Calling him names means you stooped to his level.
I know but I'm going to taunt him and see how he reacts.
You care about this guy, don't you? Why not just put it behind you and try becoming friends again? You clearly care about him if you're willing to put in so much time to be rude, and this way you could maybe stay close.