1-AA, I don't envy you dealing with guys like FB93. Although he acts like a child, I assume he is full grown child, with a real chip on his shoulder. My guess would be he has a repressive boss and has to say "yes Mr. (or Ms.) Jones" all day and is looking for someone he can be rude back to with impunity. I suspect that, want to or not, you’re eventually going to have to block him. Even contrarians like Paladin make thoughtful comments and aren’t always rude, crude and insulting. They make you think, not like this guy. Glad this clown is your problem.