Alright, lets make this nice and simple. Report all of his posts that are offensive, rude, etc., and don't give him a sarcastic, rude comment back either. Instead, when his post is found, after you report it, if you still "just have to" reply, then at least post something that is helpful to the thread and you can tell bluto (or anyone else that is rude for that matter) that it was unnecessary behavior, then just wait for a mod. Thats probably the best way to go. After a while the user will either stop or be stopped.
Itsme