I'm going to ghost my best friend
Why would you ghost a friend?
I know him so well and he will be upset.
He would be upset if you suddenly ghost him. It's bad to tell someone that you aren't speaking to them on purpose. They would not trust you again.
It's just a game and I have to have my fun somehow.
I don't think this is a good way of having fun. You are really going to hurt your best friend in the process if you choose to do this.