There was nothing in the case law. It wasn’t surprising. Celestia had just skimmed it—to really review a millennia of cases would have taken her months—but none of the summaries mentioned blocking rings at all. It was so rare to even have a unicorn prisoner—she could count on one hoof the number of powerful unicorns they’d had to imprison in the last century. Each one of them had been powerful, and each one of them had done terrible things. One had nearly managed to start a war with the buffalo; she was part of the reason why the buffalo and Appleoosans didn’t quite see eye-to-eye. Celestia filed a quick mental note to make another attempt to set up an embassy: the last few attempts had been rebuffed, but perhaps Little Strongheart could talk her father around.