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To be fair, such an oversight was in some respects understandable. Though the art of shapeshifting was theoretically possible for any being with significant magical reserves, it was considerably less intuitive than the magic earth ponies used to coax abundant crops from the ground, or the weather manipulation magic of pegasi. Meanwhile, unicorns tended to find it much easier to cast glamours to disguise themselves when they needed to alter their appearance; it was far more practical than devoting oneself to learning the ins and outs of a completely unfamiliar aspect of magical theory. That said, Sunset had difficulty believing that she was the first unicorn to come up with the idea of shapeshifting out from under a magic inhibitor, so her first task was to figure out what was keeping all the other unicorns in Ft. Featherworth from attempting this themselves.

A few hours in the prison library revealed this obstacle to be the restriction of information. Granted, Sunset hadn’t exactly expected anything with a title like Shapeshifting for Morons any more than she would have expected manuals on crafting a shiv, but there were chunks of standard reference works that had been redacted with black markers to avoid providing any information on shapeshifting beyond occasionally admitting that it was possible. Presumably, the idea was to deny inmates access to the theoretical grounding that would allow for effective experimentation. Sunset briefly wondered if this had the makings of a potential civil liberties lawsuit, but she decided against it. After all, even if she could find a sympathetic lawyer who could actually win, it would still mean revealing her intentions, which would only result in extra scrutiny.

https://www.fimfiction.net/story/387132/2/manifesto/2-exploration