It looked a bit like a flamewar, with Yhorian feeding the flames. I hope that something is learned from all this commotion. You made your condescending post and after he responded with the drunken(?) post containing the flame, you said that you did it for the sheer fun of ticking him off. Sarcasm or not, Yhorian took it just as you wrote it and took it that you are biased and hateful towards him and thus stopped listening to you. Yhorian mistook you for a biased troll that is best banned. Such individuals do exist and can be disruptive to the forums if they are allowed to post. The banning guideline is pretty much that people who don't know how to behave on the forums and thus disrupt it are removed from the forum. I admit that I didn't get his intent before, but I think those posts of yours were the ones that caused the potentially disruptive individual interpretation and thus, the ban warning.

The likely factors that lead to that interpretation:
-You flamed Yhorian by calling him dumb, adding a condescending tone to your post
-You later posted a post saying that you love griefing him.

Granted, the posts had some valid content too, but the tone was what led to the misinterpretation and the ban warning. I'm pretty sure that this is what happened in the situation. I suggest that you both just agree that you misunderstood each other and drop all bias that might be there.