Cheating. We have again maintained that we are NOT providing a closed ecosystem. Again, there are other games that do this - and they were willing to shoulder the tradeoffs that you MUST MAKE to provide this. We weren't interested in those tradeoffs or that burden. They were not in keeping with the kind of game we wanted to make. We have never pretended or proposed that we would make a closed game and have been at great pains to make sure that people understand we are NOT providing it. We have endeavored to give you tools to play with only the people you want to, and to eject cheaters from your game and never see them again.