I don't wish any physical harm to come to the user behind these alts, and I'm reasonably sure you don't either.
However, I think it's good that he hear the message that he should stop messing with people on the site in the strongest and most forceful way possible.
^ Note: The above sentence contains an example of the subjunctive mood: "that he hear." Please notice how altering the tense of the verb in the main clause ("I think it's good") would not alter the use of the subjunctive mood in the subordinate clause. For example, I could say "I used to think it was good" and I would still use "that he hear." :D